My mom has a master's in math, and she can solve complex math problems, but later, I learned how difficult it was for her to apply this knowledge to solve real-life problems. After I became an engineer, I realized how difficult it was to figure out what mathematical approach you can use to solve problems. That is when math becomes exciting and fun.
What I had in my curriculum was just mugging up formulas, without understanding why's and what's and the significance of the concept. I'd just mug up formulas and patterns of questions and apply the methods for such questions. Now I'm 24 and want to learn how to learn math intuitively. And my question is how'd you start from scratch?
@@julians9070 sometimes,it is not necessary to follow these steps , but understanding the general rules ,the patterns of things around you is better , may be you have a big ammount of knowledge , but you are not that wise . that what i'm trying to say, yes you learned things you are conscious about them , but how does this affect your thinking, how can you find similar patterns in other domains etc , this is why we say a good mathematician is a good physician is because of his general understanding of things .
As 73 year old studying math for the first time and having a mechanical background your analogy is crystal clear and very logical. Thanks for taking the time to put your thoughts on line. With the tube question I would telephone the org’s engineering section and ask them for the total length.
The roads probably get more use with cars than the tube and the tube requires a great deal of infrastructure restructuring to bring to fruition. I’d say the roads are produced more than the tunnels, so I’d use the miles of roads as an upper bound.
Absolutely fantastic recommendations, literally the best, I am in fact now going through these books and it's incredible how much it differs from the standard education I had
Heyyy, thanks for your comment! I’m very happy to hear that you like these references 😁 yeah, I wish I had known about them already before high school. But it’s never too late. Best of luck to you!!!
Indeed I did buy them all. It can be expensive, especially if you don't live in the US, but if you like math, and want to get really good at it, I can highly recommend.
@@ElijahHemingway I was referring to their books specifically such as: Introduction to geometry, introduction to algebra, introduction to number theory, and so forth and then their intermediate books as well, plus NT course. All materials are really good.
Math is actually at least two skills or disciplines. One is understanding the concepts. The other is being able to solve problems involving them. I would argue that the former is not quite as difficult in terms of sheer work required to develop as the latter. A lesson I learned much later than I would have liked to, owing to my personal history. Learned from bitter experience. Which also shows that luck counts, too. Hard work and luck are not totally independent variables. They can influence each other.
Thank you brother. I went to a rural highschool with teachers who were poor at their jobs, and therefore put me behind. Im re teaching myself math from algebra all the way up through calculus currently so i can hopefully get into school for engineering next fall. This helped tremendously
Good for you. But fair warning, the math books from “The Art of Problem Solving” are geared to train future professional mathematicians. Meaning, they attempt to teach you to think in terms of doing mathematical proofs for everything. That is fantastic but I don’t think that will make you proficient quickly enough, because it will take a couple years for you to transform your brain to think in that way. Instead I would recommend you get two books from Saxon Publishers, by John Saxon, along with the solutions manual for each: Advanced Mathematics, and Saxon Calculus. I’ll explain why I think these books will prepare you better. Just as this video explained, normal math books teach you a new concept in one lesson (he called them “tools” in the video) and then move on to a new topic in the next lesson so you never really get to truly master the previous “tool”. The Saxon books are different than any other books I know of because the homework problems for any given lesson includes problems from the previous lessons. In other words, the problems for lesson 56 will contain problems from at least 15 previous lessons, and they will be a little harder than they were in the lesson you first learned those concepts. By the time you get to the end of the book you will be doing trig, algebra 2, pre-calculus, and calculus problems almost as automatically as if someone asked you “what’s three times two?” The secret is to do every problem. If you get stuck, don’t waste a ton of time going trying to figure it out. Instead go to the solution manual, study the step by step solution, close it, then do the problem again, remembering each step and duplicating the solution. That method will train you in both problem solving techniques and how to think mathematically. And while you’re at it, since you are going for engineering, get Saxon Physics too. I promise you if you can do every problem in all three books you will crush every subject in your engineering studies.
@@ccriztoff Dude. What’s wrong with you? He’s here making conversation with the video creator, thanking him, and he’s trying to learn math on his own. But you gotta butt in to dis him - a complete stranger minding his own business? Instead of lecturing him maybe you need to take responsibility where your parents obviously didn’t: teaching what constitutes appropriate manners and conduct.
For the London Underground problem I would first of all aim for a rough ball-park figure. I'm also too lazy to take any train speeds as inputs. Looking at the Underground map, I'd like to simplify it further by imagining the network as a set of pure horizontals and verticals. The total length is then just the sum of H horizontals plus V verticals. Let's also consider the map's rectangular shape, so a horizontal is e.g. 1.25 the length of a vertical. How wide is London? Let's say 20 miles? So a horizontal is 20 miles, a vertical is 16 miles. For our "raster" Underground, let's pick 5 for the number of horizontals, and 7 for the number of verticals. Total? 5 x 20 + 7 x 16 = 212 miles. I still don't know what the true figure is, but I expect the real length to be closer to 212 than 21,2 or 2120 miles. Quick Google check.. 249 miles.
Hello. I understand why a horizontal is 20 miles. It is an estimation, a proposition. I also understand why a vertical is 16 miles. Since a horizontal is 1.25 the lenght of a vertical, the vertical is 16 miles. Nevertheless, I do not understand why you have picked up 5 and 7 for the number of horizontals and verticals, respectively. Could explain it to me?
I think intuitively understanding probability is the most useful specifically, understanding the compliments of probabilities, which is super easy honestly. Understanding the compliment of a probability will completely change your mindset when coming across a statistic.
@@rapoliithe didn’t mean a compliment in the sense of niceties towards probability. He meant a COMPLEMENT, which means the complementing probability to something. You will understand immediately: If the probability to win in your favorite game is 10%. Then the complementing probability is 90% which is the probability of loss.
Yep, this resonated with me. I did pretty average/crappy in my engineering undergrad because I didn't know how to learn. Like you said, it just felt like memorizing procedures and very little of it stuck with me in a way that could be extrapolated to novel situations. Too many concepts immediately obscured by dozens of symbols and pages of rearranging equations. That was intimidating and prevented any confidence in thinking that I was grasping any of it at all. In retrospect, after figuring out how to learn new things, the underlying concepts of the stuff that used to terrify me are embarrassingly simple to understand. I think a lot of professors are super smart in their field of study, but very little of their brain power goes to thinking about teaching and how people actually learn things. I can say that because I also had a few professors that were really good teachers and I remember everything I learned in those classes.
The key is to be humble and not be scared to afmit that you've missed a few steps during school. Start again so that you're ready to face greater challeges with the assurance that you have the necessary tools now.
@@w花b Yea, I'm good now in terms of confidence and humility. The humility has always been with me, to harmful degrees. I had to build up the ego and integrate it to some degree to come out on the other side. I had to be forced to come up with solutions on my own without me seeking direct guidance. I had to see that when I come up with solutions on my own, they are often praised by others who I regard much higher than myself. I just wonder how many people are running into psychological software limits while thinking they are running into hardware limits. Sometimes I think that psychology and philosophy should be major parts of the curriculum in any technical field of study. Not only for personal self-development, but to provide much deeper insights into the study than can be provided by technical analysis alone.
@@LCC2731 When I'm feeling overwhelmed by a technical explanation, I make sure to stop what I'm doing, and then really focus on trying to understand the simple underlying concepts. I try to build an intuition for the underlying concepts by searching for explanations written in plain English or with simple diagrams (minimal math, minimal symbols, minimal technical jargon). There's so many great/learner-friendly sources of information out there these days. And I might look at multiple sources to confirm that I am indeed on the right track in understanding the concept. Once I've gained a decent intuition, I use it as a roadmap to guide my interpretation of the mathematical formalisms that were originally overwhelming me. Knowing that I have to take the time to do this ultimately adjusts my expectations of myself to a more realistic level. A lot of feelings of frustration, intimidation, imposter syndrome are due to starting off with unrealistic expectations of yourself. And it's easy to get frustrated if you're comparing yourself with others and how quickly they appear to "get it". But you have little idea of how much time/energy they've previously spent learning the concepts or related concepts. So even if you're exposed to the same information at the same time, those who know how to learn and those who have already put in some time to understanding will appear to be much smarter/quicker than you. I think a lot of that is an illusion. To use an engineering analogy, each of our brains have very different initial conditions (which are hidden). Also, spend extra time on understanding fundamentals. For example, since I'm in electrical engineering, I spent some extra time understanding Maxwell's equations (there's only 4 of them) and surface charge distributions in the context of electrical circuits. Knowing how electrons fundamentally behave on a conductor, behave within electrical components, and behave with different excitations (high frequency vs. DC) allowed me to build a decent intuition that can be applied to any situation. You begin to realize most of the complexity and the conceptual breadth of your field of study comes simply from different configurations of a handful of fundamental concepts. But when starting off in a field of study, you may not understand this and it will look like everything is conceptually disconnected from itself. That's how it was for me in college. It just felt like everything was disconnected, loosely related, and as a result, very little of it stuck with me in a meaningful way. At the time, I simply learned what I needed to pass tests. I think a lot of people experience this. Hopefully that wasn't too jumbled of a stream-of-consciousness. Just pick and choose the things that resonate with you. Sometimes it's just one or two sentences in a wall of text that really resonate with your current state of mind. Hopefully some of it helps.
Your series of comments are amazing. I'm an undergraduate math student and sometimes I feel like I've hit my limit with my grades. I need to build up my ego, understand the basic stuff and force myself to stop memorising Definitions and formulae.
Thank you for explaining in a calm and friendly way. It really makes difference in how we can view mathematics as something helpful and not just bunches of information to be decorated. Hope you can keep spreading acknowledge and helping many people like me who is trying to relearn this amazing topic. Take care x
Ich war auch nicht gut in Mathe, aber tada, bin ein theoretischer Physiker geworden. Ich habe erst ab der 8.Klasse gemerkt, dass wenn man sich hinsetzt und übt und übt, dann merkt man in der Klasse wie weit fortgeschritten man ist und wie sich das bemerkbar macht in Form von Lob eines Lehrers. Erst im Studium merkte ich, je mehr Mathe ich mache, desto mehr Spaß macht es. Das war davor für mich nicht so denkbar, dass das Freude in mir auslöst :).
Hätte mal eine Frage: Seitdem ich anfing mit dem Informatik Studium wollte ich meine Mathe Skills verbessern. Desto mehr ich über Mathe herausfand desto mehr wurde mir bewusst, wie wenig ich eigentlich kenne und die Themen scheinen endlos zu sein. Kommt man später an einen Punkt wo man sagen kann, nun verstehe ich alle Mathematischen Gebiete? Fühle mich so überrollt.
@@UberBossPure Eigentlich nicht ganz, aber es fällt dir viel leichter in andere Gebiete einzulesen. Die Grundmodule in der Mathematik sind wichtig und dann versteht man die fortgeschrittenen Themen besser. Vor allem in Physik, Informatik wo gewisse Ideen Konzepte uns mathematisch irgendwie bekannt vorkommen. Pure Mathe geht schon über viele Aspekte vorbei. Da gibt es mathematische Gebiete, wo sich nur ein handvoll Leute aus der ganzen Welt sich auskennen. Aber du musst für dich wissen (als Informatikstudent), was willst du später machen und welche Mathematik würde man brauchen. Für Physik viele Differentialgleichungen, riemannsche Geometrie für Allgemeine Relativitätstheorie, oder vllt Topologie für Kondensierte Materie Physik. Du musst schauen, was du brauchst und dann verwendet man die Konzepte für deine Forschung und deinen Erfolg.
I've recently got interested in math again, and I find it amazing how it appears in many areas. There's also many solution to one problem, but I like to think with simplicity. If not only I can solve a problem, but explain it to others, then it's a simple solution. I feel like if math is taught correctly, people can see a form of beautiful art in it too. The best if you can find answers logically and intuitively as well.
I'd calculate the length as the London tube 🚂 as follows: (Assumptions) A1: I'd model the London city as a circle with radius r=10km (that would be my guess, i've only been to london once). A2: And let's say we have approx. 1 station per km² (also a rough estimate :D). (Calculation) The area of a circle is pi * r^2 = pi * 100km² ~= 300km². -> we have approx. 300 stations (because of A2: 1 station per km²). Each station has 2 neighboring stations, so with the number of stations n, we have n-1 km = 299km for n=300 of tube. Let's round that and conclude London has approx. 300km of tube if the assumptions are approximately correct. (Solution) I looked it up and London has 402km of tube. That's a relative error of (402-300)/300 = 1/3 (=30%). I'm happy with that
The Tube system in London is build in a very simple fashion. There’s lines which go horizontal (east to west vice versa), lines that go vertical (north to south). All the lines kind of meet in the middle of the city (downtown). So it kind of resembles a circle. The really roughest way would be to take the area of London and pretend that it is a circle. Then calculate the diameter of that circle and multiply it by the number of tube lines there is. Kind of creating a wheel with the spines being the lines that go through the city and the outer ring of the wheel being the borders of the city. The way I’d go about it is creating an estimating models. I’d take the width of London (roughly east acton to Stratford) and height (roughly Barnet to Mordon). From here on out it depends on how sophisticated you want to model this problem. The simplest way would be to count the number of tube lines London has and multiply this number by the average length and width of the city. If you want it more sophisticated you could count how many horizontal and vertical tube lines there is and multiple these amounts with the width respect length of the city. You could also go ahead and get more sophisticated by iteratively aiming towards a more precise recreation of reality. You could model out the circle line as a the circumference of a certain diameter within this model. To consider things like curvature of the tube lines I would just estimate a 20-30% add on top of the length and width basis we used
@@SamuelBoschMIT Danke mein Freund! Hoffe ich auch für dich. Großartige Einstellung die du hast. Vielleicht läuft man sich ja irgendwann über den Weg. Bewege mich auch in der Finanzbranche
I enjoyed reading this very much. I’m a programmer that at age 40 nearly just got into math (because of computer science stuff and general interest) You have any books you’d recommend for folks wanting to start over and build up
Finding the length of the London Tube system involves measuring the total length of all the individual subway lines. The London Underground consists of several lines, each with its own length. The best mathematical solution would be to add up the lengths of all the individual lines to determine the total length of the entire system. Obtain the length of each subway line: Research or use official sources to find the length of each individual line in kilometers or miles. Sum up the lengths: Add the lengths of all the lines together to get the total length of the London Tube system. Total Length = Length of Line 1 + Length of Line 2 + … + Length of Line N Total Length=Length of Line 1+Length of Line 2+…+Length of Line N
I have naturally learned these skills over the past year or so in my persuit of a maths degree. Although I personally found it much easier to find these skills by basically being talented at mathematics, lowering the time it took for me to completely understand and gain new tools. Like a 60 unit hour course in linear algebra was completely sufficient for me to understand most all of the material, from the most basic applications of matrices to vector spaces and eigenvalues. All the fun stuff which would normally be too quick for most people to pick up, I simply applied myself for hours on end and learned the material effectively. That’s kind of what this video describes, it just says “learn it and then you’ll know it” circumventing the fact that plenty of people are just genuinely bad at math, because they have a low aptitude for abstract reasoning in general. Perhaps I’m being too negative but this approach hand waves away the biggest problem of natural ability, and people struggle with math despite spending time to learn the concepts because they don’t have that aptitude.
>That’s kind of what this video describes, it just says “learn it and then you’ll know it” circumventing the fact that plenty of people are just genuinely bad at math, because they have a low aptitude for abstract reasoning in general. Hello, Rigo. Yes, the video in question did not address the lack of abstraction. However, it is important to note that abstract reasoning is a skill (not a fixed genetic trait) that can be trained, developed, and refined. The key to achieving success in mathematics lies in identifying the right approach. Therefore, the use of the term "aptitude" is not entirely appropriate in this context. In reality, almost anyone can acquire proficiency in mathematics, and topics such as Linear Algebra and Analysis are often considered basic, trivial and straightforward within the higher-level mathematical community (no offense). With that said, the reasons for individuals failing to achieve success in these subjects are typically related to other factors such as laziness, lack of discipline, inadequate education systems, cognitive biases including anxiety, imposter syndrome, constant comparison to others, or aversion, insufficient motivation (worth noting that there are relevant studies on the subject, such as hypofrontality, ADHD, behavioral addictions (which are increasingly prevalent in our modern society), etc.), flawed learning methodologies, knowledge gaps, lack of interest, unrealistic expectations, or an unsupportive environment. Additionally, in a world where computers and machines can automatically solve problems, there is a tendency towards complacency among many individuals, leading to a reluctance to engage with concepts that machines can easily process in a fraction of a second. Studies have been conducted on this phenomenon, known as "Google Syndrome," which can also be applied to other fields. Neurology did also shed light on these issues. _Perhaps I’m being too negative but this approach hand waves away the biggest problem of natural ability, and people struggle with math despite spending time to learn the concepts because they don’t have that aptitude_ Your statement may create the impression that this issue applies to the majority of people, while this is not the case at all. There are certainly rare cases of individuals with severe mental handicaps who may face significant challenges in mastering mathematical concepts. However, these individuals often struggle with communication, basic conceptual understanding, and other fundamental skills that can make learning mathematics difficult. In any case, it is unlikely that such individuals would pursue higher education, so they do not represent the "average" student population. The video in question is addressing the average Joe or Jane, and it is reasonable to suggest that such individuals are certainly capable of grasping concepts in linear algebra and analysis, provided that they approach the material correctly. _[...]and people struggle with math despite spending time to learn the concepts because they don’t have that aptitude_ Once again, this assertion of yours is, for the most people, incorrect. In fact, aptitude is often the least consequential factor, the least of the problems in explaining why individuals struggle in mathematics. Rather, the primary factors that account for failures in these subjects are often more complex, including behavioral addictions, such as those involving pornography, social media, or being chronically online in general, and the tendency towards instant gratification that characterizes a major part of our modern society. These behavioral addictions have been shown to contribute to hypofrontality, which can have profound effects on the brain's reward system, and thus, necessarily on the ability to learn, to concentrate, to abstract reasoning, etc. People didn't believe this at first, and since it is so prevalent nowadays, because people are "used to it", they don't even notice the consequences arising from this. In the past year, these concerns have received official recognition, with the International Classification of Diseases, Eleventh Revision (ICD-11) formally recognizing compulsive sexual behavior disorder (CSBD) (Remember: People laughed about this, admittingly because certain religious sects use the empirically verified unhealthy nature of pron addiction to further their cause of religious living). The negative impact of such behavioral addictions on learning is then often compounded by the pace of modern life, which emphasizes speed and immediacy over deliberation and depth of understanding. In the past (say the 50s), individuals who wished to research a question or topic were required to visit a library and sift through multiple books, which encouraged thorough reflection and deeper engagement with the material or think about it entirely themselves without assistance. By contrast, in today's world, people are often satisfied with minimalist, on-point and immediate answers that require little effort or time investment (just look at this video or other video essays and for the comments that "summarized" this long video and then see how this summary often misses the in-depth idea of what the video is trying to say, but people still being satisfied and thanking them "for saving them 30 minutes" => Necessity for fast answers, symptomes of impatience, etc), which can lead to factual knowledge without a more profound understanding (which is why I have a personal dislike of "fact checkers" that even more so encourage this behavior). This minimalist attitude and lack of attention span can also be observed in the popularity of platforms like "UA-cam Shorts" and "TikTok" compared to longer video content that is often skipped. Admittingly, the average person has less free time to devote to a particular subject nowadays, making it more challenging to engage with complex material fully in length. In other words, this modern trend towards instant gratification has become so pervasive that individuals who reject this approach are still often forced to conform to it. People *still* (despite the vast amount of research in neurology and existing brain scans) underestimate how severely the age of the Internet influenced and still influences our brains. Therefore, average individuals who might have succeeded in the 60s with linear algebra and analysis may struggle in the present due to the constraints imposed by modern society, Internet and educational systems. The introduction of the Bologna Process and the adoption of bachelor's and master's degrees in Europe and Germany have resulted in the boiling down and confinement of knowledge into shorter time frames, making it more challenging for average individuals to engage with material comprehensively, therefore ultimately elitizing academies for the few talents who can keep up with the modern pace. In contrast, in the past, diploma programs allowed for more extended periods of learning, which facilitated deeper engagement with the material, allowing even the average Joe to confidently get a degree without being a fast-learning genius.
@@Kaje_ Are there amazing books, spectacular tutoring programs and other wonderful resources you'd like to recommend that can enable one to master the fundamentals of math?
I am a student taking a course specifically to become an engineer, but sadly am poor in my maths but still am going to make my dream come true by understanding, remembering and practicing 😊
This is absolutely terrific. I believe that this could crack the code with public schooling in general. Couldn't it be explained that the height of education is intuition? Intuition being the accumulation of knowledge, wisdom and creativity. I'd love to have a real discussion on this because we must know how to develop our intuition if we hope to progress as a species. Unfortunately, the modern school system has failed us.. math was never explained to me in this way and I struggled.... But now, all of a sudden, math is being explained in an intuitive sense and it's clicking with me. Now let's try and translate intuition to the other academic pillars. This is just so incredible!
Beautiful insight, and I totally agree with you @David Walker 👏🏾 I think math, like a lot of other subjects, can be cultivating as a natural part of understanding the world - it’s even, in fact, touted as the first natural science. As intuitive and creative as we can be, I think everyone has the potential and capacity to do math - math, as universal as it is, is not reserved for some exclusive club. I enjoy fostering the math intuition within every student I work with as a math tutor. ☺️
Great video, Samuel! As someone who studies math, I totally agree with the mindset-part. But a lot of time it's not even a person's fault but the fault of their teachers/parents etc. who tell them that "math just isn't for them" really early on (or even worse, there are teachers saying "math isn't for girls" which just excludes half of the population).. One of my friends at uni told me that some of his teachers in elementary school said the same thing to him but he was lucky to have a physics-teacher in 6th grade who really encouraged him to understand physics and math and in the last few years of school he even went on to win some national & international math-competetions. For the tube-problem my thought would have been the following: I know that Berlin has a diameter of roughly 40 km with a population of around 4 million. I also know that London's population is around 9-10 million (let's just assume 10) and that London's population density should be a bit higher (I would have guessed by 20%) since Berlin is really spaced out. So London_Pop/Berlin_Pop = 2.5 and London_Dens/Berlin_Dens = 1.2 which means that London_Area/Berlin_Area = 25/12; therefore Londons diameter should be sqrt(25/12) which is close to sqrt(2) which is close to 1.4 times the diameter of Berlin, so around 56km. I would also expect that the tube does not go to the edges of the city as a tube system is usually built for the parts closer to the city center so I would subtract 10 km from the city's diameter to get the tube-system's diameter. (This would be around 46km now) I also know that Berlin has 3 lines which, kind of, cross the whole city (so their length would be close to the diameter of the tube-system) and another 5 which only cross half the city. I would just double those amounts because, while London's population is 2.5 times the population of Berlin, I also think that London's tubes have a slightly higher frequency than Berlin's so that makes up for that. With all these assumptions I would therefore arrive at 6*46 + 10*23 = 506km. This certainly isn't the best guess but it works without knowledge of any city's rail-length.
Hey Leo, thanks for the comment and sorry for my slow reply! Yes, I completely agree! It’s so easy for a teacher to discourage someone from going in a certain direction, but so difficult to motivate people to do so. Especially the example you just mentioned Also, good job with the estimation process - I really like your answer! 🙂
If a teacher tells girls that maths is for boys. Tell the teacher to look up the name Ada Lovelace then ask if they still think their statement holds true!
My dad and I would try to learn math when I was little and it never worked out. I guess I always wanted to do something else or he wasn’t great at teaching it. So basically throughout my schooling and as I was going into collage he would say but you can’t do the math and I decided against classes with math or even trying a class with math. Now I graduated and thinking back that I could have done the math and not I’m stuck doing something I’m not that interested in. I had one small math class when I was at college and came out top of the class of 14 students. Not huge it was simple math but I realized I could do math.
For the tube problem, i took a fairly simple approach. I once took the track from Heathrow to downtown which took around 1 hour (on average it seems airports take a rough 1 hour by transit). Assuming an average speed of 40km/hour this would be around 40km of track. I know that line extends beyond my stop so just guessing that that line is 60km long. Starting from there, I remember 8-10 colors on the subway map which indicates around 10 lines. Now I’m guessing heathrow line is one of the longer ones so let’s say the average line is around 40km, times 10 lines gives us 400km of total line. Now tunnels are generally underground in the city and overground in the suburbs, I’m guessing central London is about 40km in diameter while the total tube coverage area stretches 80km in diameter. Thus Longer lines are primarily overground but more sparse while shorter lines are primarily underground but more frequent. These effects should mostly cancel each other out so around 40-50% of the total line should be tunnelled which gives a range between 160-200km!
My lecturer of physics used to tell us that there are 3 stage of learning a certain topic in this ascending order. 1. Understanding 2. Telling 3. Writing
Total length of the london tube tunnels, multiple approaches: 1. GoogleFu - this information is probably available as a statistic on the internet = 249 miles 2. Map (Paper of Digital) - Assuming tunnels are relatively straight between stations, measure the straight-line-distance between each tube station, for every line, sum this all up and add 10% as error 3. Tube Timetable - will show average transit time between stations. Some of this time is speed up, max speed, slow down, stop at station. Lookup exact distances between a subset of stations, and generate an approximate formular for transit-time vs distance on different lines. Then apply this to the entire timetable. Issues: - There is probably some missing information related to disbanded tunnels, ancient unused stations, and tunnels to non-public train depots. This might requires adding on a percentage as an error factor. - Question specifically said "tunnels" and not all the tube is "underground". Google maps might be able to show you where lines switch to being above ground.
After studying Algebra, geometry, trigonometry and statistics., proceed to number theory, vector calculus and abstract algebra. Lambda calculus can be used in computer programming.., matlab.., binary it's awesome! Mathematics is the language of everything! 🎧🎶🤩
The radius of greater London is about 45 miles. This makes the circumference about 270 miles. Imagine each tube running from the center out 45 miles to the urban perimeter. You need enough tubes so that one need not walk too far to get to a tube station, so guess about 4.5 miles between end stations on these radially arranged tubes. Each tube is thus 9 miles apart at the perimeter. But nearer the center you don’t need as many, so the number is cut in half every 9 miles. So there are 9x30 + 9x15 + 9x7.5 + 9x3.75 + 9x2 or rounding to 9 x 57 = 513 miles of tubes.
Here are a few strategies that might help you learn to understand math more intuitively: Start with the basics: Make sure you have a strong foundation in the basic concepts and principles of math before moving on to more advanced topics. This will help you better understand the more complex ideas that come later. Practice regularly: The more you practice solving math problems, the more intuitive your understanding of the subject will become. Try to work through as many different types of problems as you can, and don't be afraid to make mistakes - it's all part of the learning process. Use visual aids: Diagrams, graphs, and other visual aids can be very helpful in understanding math concepts. Try drawing pictures or diagrams to represent the problems you're working on. This can help you see the relationships between different concepts more clearly. Work with others: Collaborating with others can be a great way to improve your understanding of math. You can bounce ideas off each other, explain concepts to one another, and work through problems together. Experiment with different approaches: There may be multiple ways to solve a math problem, and trying different approaches can help you find the one that makes the most sense to you. Don't be afraid to think outside the box and try something new. Seek help when you need it: If you're struggling with a particular concept or problem, don't be afraid to ask for help. You can ask your teacher or tutor for clarification, or seek help from online resources or study groups.
For the benefit of others interested, let me share two obvious titles as a first read. 1. A Primer for Mathematics Competitions by Zawaira & Hitchcock (A recent Googling pops up a couple of similar titles but I am unfamiliar with those.) 2. The Art and Craft of Problem Solving by Paul Zeitz
This was a fun problem, I've been seriously studying mathematical fundamentals since the start of the year. I imagined London as a circle with radius 10mi. I cut the circle into 8ths with 4 lines, and I cut it again into an arithmetic series of circles from 2 miles to 10 miles. Then you just sum up everything, 60•pi mi + 80mi = 268.4 mi. I looked up the actual number and saw 250mi online. Anyways I hope my math checks out, but I was happy to get the right solution. A few months ago I wouldn't know where to start :).
Sweat the small stuff, and never be afraid to go back to basics. As Tobias Dantzig wrote in his book 'Number : The Language of Science ( which I highly recommend ) : ' Why is it that only mathematical processes can lend to observation, experiment, and speculation that precision, that conciseness, that solid certainty which the exact sciences demand ? When we analyze these mathematical processes we find that they rest on the two concepts : number and function ; that function itself can in the ultimate be reduced to number ; that the general concept of number rests in turn on the properties we ascribe to the natural sequence : one, two, three'.
I see London as a circle with diameter of 25 miles. I take the center as hotspot which most of the railways crosses. Then I take 8 lines through the center point (like a pizza with 8 pieces) since I would build a railway in a city this way since the density of the traffic is and should be more center focused. Additionally I put 1/4 (7,5 miles) of the diameter in the middle of every piece on the outside since in the outer regions are connected to weak since with further distance from the center railway connection gets separated to far with too big radius. So I come to a result of 8x 25 miles + 8x 5 miles = 240 miles
My solution to the tube problem: The tube trains average speed is 33Km/hr. Find the total time it takes for each train to travel it’s entire line and add them together, formatted as a decimal of hours. Then multiply that value by the average speed (33) to get an average of the total distance of the tube line.
The problem with School and college tuition is that its a factory. You are sorted into your supposed intelligence then you get trapped there. Depending on what conveyer you are on you will only be given the course material to satisfy a pass for your stream. Everything is pace and grades, the actual knowledge gained doesn't really matter. The big problem is that textbooks also follow this as well, the books just target the exams or levels to be studied. Continuity which is so important doesn't seem to exist. This of course is partly due to the physical size of a book. In the UK it was very hard to learn advanced shool maths as they all jumped in at more difficult areas without the all important lead up. I found American text books so much better and I only wish I could have obtained them when I was younger, (pre Internet).
Ich habe für mich gemerkt, dass das Anwenden das Beste ist. Wenn man viele Aufgaben löst dann prägt sich dass besser ein als das Script mit den Beweisen ins Hirn zu stopfen. In den Aufgaben hat man auch viele Fallbeispiele und wenn man etwas ähnliches kennt, weiß man vielleicht wie man das lösen muss. Außerdem ist die Feynmanntechnik auch sehr empfehlenswert.
Heyyyyoooo Nosferatu, danke für den Kommentar 😉 jaaa, Feynmantechnik ist super. Leider musste ich auch so viel auswendig lernen im Studium. I’m gymnasium war es viel besser
For the tunnel problem solving I will check the radius of London. I will calculate the length of a line using the assumption that it crosses the whole city usually lines make , then I will count number of lines and I'll multiple the length of a line with the number of lines ,and if I have a map of the tunnels maybe will give them some 5 -10 % bonus because metro trains don't go always in a straight line , that's my 4 grade math solution 🤣
I think that we gain intuition (a feeling how to solve the problem) when we do some memorable examples (about some physics; a different way of doing the geometry) and reconnect the idea using space repetition (explaining to a 5yo). And not doing a bunch of exercises in a day; maybe that after you have understanding and test your new tool set. Interconnecting ideas related to different subject with wide scope (hate when say I leave that to your physics teacher or that is part you will see in probability), not isolated pure math. I kind get some of that on edX.
take hillingdon as "x" and havering as "y" Take into consideration of all the routes from x to y from the tunnels london's public transport system. find the length of each route. and lastly add them all up to find the total length of all the tunnels. thank you
In my secondary and high school I absolutely hated mathematics but recently when I understood the reasons behind the formula and standard forms, my interest in mathematics bloomed! Can someone help me find the resource to understand mathematics better? Thank you mate for the resources and video!!
Use the scale given on the map to measure the separare lengths by a ruler or a measuring instrument. Do the conversion for each and total the individual results for each to determine the actual length of the tube.
the way i would estimate the length is first thinking about the size of London. London as a circle should roughly have a diameter of 40 km. Since the density of the tunnels should be higher in the center of the city i thought of a tunnel strucuture similar to a star (first draw two straight tunnels across london that look like crosshairs then add another two tunnels splitting every quarter of the circle(London) so that london looks like a pizza, and then another four tunnels that split every eighth of London.) That makes 8 tunnels with a length of the diameter of London which is 40 km which results to a total length of 8 * 40km = 320km
Very interesting solution! Yeah, I never even thought about this. But of course, the tunnels should be structured in a certain (logical) way, so this is a very smart estimate 🙂
to solve the 'tube' problem i would first know the total height of the tunnels and the length and the would use the formula of curved surface area of a cylinder by breaking it down and then would add all of it to get the area the reason why I chose curved surface area is because he asked the area through which the train goes but not how much can he put into the tunnel.If i am still wrong correct because i tried my best :))
i dont think people thoroughly understand math, they just do what they know as right. for example, i didnt understand how fractions with different denominators were added, i just did what i knew as right. now i know why it works.
I love the series "Everything you need to learn in a simgle fatbook" and the series "Fundamentos da Matemática Elementar". The FME can teach you from the basics in math (from probability) to some things more complex (like introduction to calculus). The geometry books, for example, have 1400 geometry problems (really). It has 11 books, but only in portuguese language
Ich finde die Gesamtfläche von London heraus (1.572km^2). Ich Male ein Rechteck auf ein Blatt Papier und nehme an das das Rechteck London ist. Den Rechteck gebe ich die Fläche von London. Ich nehme die Wurzel von der Fläche von London um die Seitenlänge des Rechteckes rauszufinden. Ich behaupte das ein gutes U-Bahn-System so lange sein sollte das man mit der U-Bahn zu allen Ecken des Rechteckes kommen kann und zu den jeweiligen mitten fahren kann. ( Wie eine art Spinnennetz). Um die Diagonalen zu berechnen benutze ich das Werkzeug der Satz des Pythagoras. A^2+B^2=C^2. Ich rechne alle langen zusammen und multipliziere das Ergebnis mit zwei weil die U-Bahn in beide Richtungen fährt. Hier die Rechnung: √1572=39.648 =40 √40^2+40^2 =56.568 =57 (2×40+2×57)×2=388 =388 =388 Kilometer Tunnel länge Weil es in der Stadt Mitte vielleicht noch mehr Tunnel gibt kann man wahlweise noch 1 diagonale hinzufügen. Wobei man dann auf 445 Kilometer kommt.
400 miles without looking anything up. But I am a Londoner. So I know there are twelve or so tube lines. Diameter of London about 20 miles. 12 times 20 is 240. But some of the lines run above ground. So call it 200 miles. It is 400 miles if you mean the total length of tunnels in both directions. (When I looked it up, I found that 55% of the system runs above ground, so that was the major error I made.)
As I am reading through different solutions to the problem, people are not actually solving the problem, they are estimating the answer. This is something that is mostly lacking in math education. In any important problem, three steps should be taken: 1. Estimating the answer, 2. Solving for the answer, and 3. Checking the answer.
My answer is to figure out how fast the train goes which should be common knowledge of the train company (mph if your in America like me, or km per hour) then ride the train to see how long it takes to go from station to station. Don’t count time between stations as they are not part of the tunnel system anyway. I’m not sure how the stations are set up, but you should be able to use all of this information to calculate roughly the length of the entire tunnel system.
For the problem, I would take out my phone and then search google. This is the best way because it has a high chance of being accurate, and I would likely solve this question in under ten seconds and get it right.
I know London is approximately 20miles Nth-Sth by 30miles East-West. I know the main lines and their very approximate layout e.g. Central Line runs East-West: therefore ~30miles. I add up all the lines and this gives me a total length of ~150+ miles. I did this mentally in ~5mins and used my fingers to add the lines (in multiples of 10miles).
i live in paris so im gonna base my answer on the paris subway : i know there are 15 lines, each line has approximately 17 stops and it takes approximately 1min 30 to get to one stop. so in total there are approximately 1245 subway stops in paris, the subway moves at approximately 60km/h so it means appropriately 1,5km per station so 1245 x 1,5 = 1873km
A typical city maybe has about 8 subway lines, each one of those taking about an hour if you ride them from one end to the other. I'd say the average speed of a subway train is 40 km/h, so that gives you roughly 320 km in total.
Thank you for your inspirational message and friendly presentation. I'm already in my 40's but I hope by picking up the textbook you recommended, and doing some of the problems in the book and online, I can refresh some knowledge and learn new ideas!
I would have nailed that interview question 😂 I just saw your instagram video and I was luckily correct even though my guess was very simple. I just estimated that the main part of london is within a 20x20km square and I wanted to calculate the length of the lines of a grid within that square. So I thought a tunnel every 1km would be too close so I went with every 2km. Therefore I summed up 10 vertical tunnels with 20km length with 10 horizontal tunnels with 20km length and thats exactly 400km. I was very surprised when I saw the true answer 😂
I just thought another solution for "The Tube" problem. I'll just look for 50-100 cities which resemble the population density of London and then take out the mean of the underground tunnels. Obviously I consider that the length of underground tunnels in these cities are known to me. And geographic factors will too deviate the mean length but still it will be a good estimate. The more cities I consider, more will be the accuracy...
For the amount of track: What I know : Taking the Thames river from the middle of London to where it opens up to the ocean is about 30 miles, and takes about 4 hrs. The city thins out about an hour into that trip. All this rest is pure guess: Maybe London is roughly a circle 15mi in diameter, packed with people. Population doesn't matter because the tunnels were dug long ago with much smaller population. it's coverage in area that matters, it has to be a short walk to a station from anywhere in that area. 1 mile of track per square mile of area keeps a walk under 10min. The area in square miles of London, plus 10 spokes from center to edge to facilitate cross town travel... the 10 spokes (radius is 7.5 miles) equal 75 miles +area pi x 7.5²miles ≈ 250.5 miles ≈ 403km of track?
2:50 tools for Lots and lots of practice Use simple tools of hammer and. Memorize steps to solve a problem. Good memorizes. For every new tool, we practice 50times. Simple toolbox Concise introduction to mathematics
I don’t know if this is the okay way to do it and I think I’m late for this but personally I would get a map of the London tube. Let’s say a 1:1000 scale. I would then at the center of every track, put a line from the beginning to the end, then measure it up and do the conversion back There is time where the tube goes right or left and not straight, that’s why I would put the line in the center, in order to get more straight line sas possible. Otherwise I should measure the angles.
i have always had good grades all throughout school,i could solve problems on paper with understanding & some meorization too. but i have realized i always lacked application of math which is why i i didnt develop love for it . Time to give math another chance & enough time
Amazing video, another one. So I think it's not my discipline but I'm highly impressed by this skills. Great work. I see forward to a video about your fitness routine! Keep going, it's great!
Heyyy Lucas, thanks for the comment and sorry for my slow reply! Yes, I would he happy to make such a video. Probably this summer already :) I just have to find a way of making it fit the main topic of this channel, given that I’m not running a fitness channel 😉
the tube problem answer is the (square root of the area of the london township) times (up line + down line 5+5) considering the circular area to project as square on the topology of earth. this was awesome! london is similar in size to kolkata, so square root of 1600 sqkm is 40km approx. So, 40km * (5+5) up and down lines = 400km tube lines thanks man for the opportunity you are cool
For context I do not know anything from the London subway system and I’m at 9th grade level mathematics. I would look at it from a top down aproach in a 2D space because even if subways change elevation the values in any meaningful way. And I would add all of the values together. But to be more precise with this I would find the area of intersections if there is any. And I would subtract it from the final value.
This video is such a gold nugget in the whole "math" youtube content! Maybe it's not a unique idea for the video but with such a elegant execution! Also sorry for my English, overall very positive about this type of content!
Hmm… to solve the problem, we’d need to define tunnels and what constitutes the tube. Let’s say that tunnels are the enclosed areas trains go through. We want to find total length traverseable by train. We know… not much… But cutting up a diagram of the subway routes, calculating the time it took on someone’s commute from a point on the line to their station and knowing the speed of the train could help us find the length of that section. We could then take the map and cut the tunnel segments into equal lengths and then calculate the length by hand, but that would take too long Very mildy differently, we could do the same thing, but then lay them in rows such that a sort of square is formed where one side is length of tunnels and the other is the quantity of them and find the area. Assuming no vents in the tunnels, we could try to pump it full of fog, and then see how much volume is used to fill the tunnels and then divide the volume used by the average cross sectional area of the tunnel to find total length We could try riding all the tunnels, We could ask repairmen or managers how long the tunnels are Or we could use good old google to solve the problem Or ask the interviewer “what’s that?” I’m not even sure my answers that good, I don’t know what we’re even given XD
Well, first, we need to estimate the entire surface area of London. Which is 20 miles long by 16 miles wide. So we do 20 × 16, which is 320 miles. Then we find just the length of one tube tunnel. Which in order to do? That's we need to measure the length of a platform on one of them and keep adding its length until we reach the end. I'm just gonna make one assumption here and say it's about 10 miles long. Finally we can take our surface area of London which is 320 miles subtracted by the length of one tube tunnel, which is 10 miles. The answer to that will be 310 miles. I don't know if this is the correct answer, but I tried my best. Edit: I have a much better solution. Do what I kinda did there but instead of getting the surface area. Let's actually just get the length and width London. Which again is 16 by 20 miles. Let's take the average length of the tube tunnel which I estimated to be 10 miles. Let's estimate the lengths of the tunnel system with the width of the tunnel system. First, we take 16 − 10, which is about 6 miles. Now let's take 20-16, which is about 10 miles. Now let's take the length times with to get the surface area, which is 6x10 is 60.
Well, here's my estimate of London's undeground: 1.1)It would be nice how big London is. Idk how big it is, but let's say it is a circle with diameter equal to the length of my city(which is long and thin, and is almost certainly smaller in area than London, so that sounds about right) 1.2) Idk how big my city is either, but i once saw in navigator app that my daily commute(almost the entire length of it) would take about 4 hours on foot. 1.3) Idk how fast humans walk, but i remember seeing that kerbals(which are smaller than humans) in the video game KSP run at 1 m/s exactly, so let's assume that's also true about human walking speed. 4 hours * 1 m/s = 14 400 m, which is about 14.5 km. 2.1) It would be nice to know how many lines there are in the London tube system. I know there is a YT Map Men song that consists of all their names(Or was it stations!? Well, whatver, it's probably close enough). I don't remember how many there are, but it was probably about 100s long. 2.2) I remember the random estimate that saying "mississippi" takes 1 second, so probably same for line/station names. That means there are 100 lines. 3) We know that London's diameter is (exactly!) 14400 meters, but how long is a line on average? Well we can assume they are straight lines, going between two random points in a circle. Which is something i could probably calculate, but that's a horrible estimate anyway, so i really don't care. Also they are not straight... so let's just say they are around 2/3 of the diameter, meaning our lines are 10km on average 4) 100\*10km = 1 000 000m. Which is my final answer. 5) Pray it's the correct order of magnitude.
I would use a square or rectangle and estimate length and width, such as 20 by 30. I would then assume there is some pattern to the tube system for it to make sense to riders, such as an array/grid and thus estimate somewhere around 400 to 500 miles, or 640 to 800 km. The problem is I have no reference for how big London actually is but I know Toronto is about 45 km across so would make an assumption that since Engand is a smaller country, London might also be smaller. Therefore I might say that a reasonable answer is 640 to 700 km.
The most important mathematical tool I've _ever_ come across, is the lowly percentage calculation. Armed with it, you'll gain an entirely new and useful understanding of the world. But... By gaining that knowledge, and using it in practise, I sadly also found out how few others employ it daily, such as professed "experts" even within medicine and economics.
I think one other way to tackle the Tube problem is by using statistics (or statistical software). Its a little bit of a cheat, but we can make some assumptions about London, if we know some numbers and how it compares to other cities. We can assume, that given the expense of underground rail, underground rail systems are correlated to the population density of a city, because economically it only makes sense to build one if enough people are using (and paying for) it. Second, we have to assume that London is not "special" in any way and city planers more or less use the same metrics and assumptions used by city planers in other big cities. With this, we can search for other cities that have roughly similar metrics like population densities, have a big population, can actually afford to build them (so only big cities in middle/upper income countries), circular shape etc. Then we can use statistical software to let the computer calculate the size of the average rail network adjusted for population size, lets say km/ per million inhabitant as our dependent variable, and things like population, population density, GDP per capita, proportion of suburbs to city center and the radius of a roughly circular city. Should give us a pretty good estimate, although that would kinda be cheating because we are not doing a back of the envelope calculation. Plus point: You can actually give them a confidence interval down to an exact decimal place.
Answer : we can run a train through all the tracks from start to end and then subtract the pre-covered distance(need to be recorded) from the new distance on the odometer .
Additional notes: 1. Read the book "How to Solve It" by G. Polya. 2. The biggest thing is to do lots of problems. Finding and joining Art of Problem Solving is basically 85% of the battle. 3. Use the Moore method for learning mathematics. This is a method of reading where you prove every theorem a book provides without reading the proof first. This can be extremely challenging if not impossible (depending on the book), but its' the best way to learn a mathematical subject. 4. Variant on 3, once you prove it your way, have a peek at the book's proof. If it differs from your's, try not to read the entire proof. Try to prove it another way. This will help you look at the same subject from different perspectives. 5. All books on how to solve things, are marginal at best. The best way to learn to solve, is to solve problems on your own. Struggle, and when you are about to give up, continue. It took me over a year to prove Morley's Theorem. I spent an 1-2 hours each day trying to solve it. I eventually got it. That is the level dedication and effort you will need. 6. Apply the Moore method to a book like Geometry For College Students by Isaacs, or Geometry Revisited. Lots of practice thinking out of the box can be had by applying the Moore Method to a good geometry book. 7. Memorize theorems and results after you have a good understanding of them. Yes, that's right memorize. That is what they do in French schools and per capita, France wins the most Fields Medals. If you don't have basic theorems and results at your finger tip, you cannot hope to tackle complex problems when you need to identify a useful theorem to use. Appreciate that you can never understand anything fully. You can only deepen what you know. Good luck.
Thanks Samuel for this video. Im from Unfortunatelly in my country my teachers don't taught me how to learn. I have finally exam for 1 year. Im close to finish mid School (it is before study in Poland ) and it would be nice to write it good. I also want to learn maths because I want to be a professional trader in future.
To solve the tube problem, first I would buy the longest tape measure I could find. Then I would fly to London and walk along each tube measuring as much as I could and marking it down. After that I would add up all the measurements and then use my phone to look up the correct answer because I would definitely be wrong.
My mom has a master's in math, and she can solve complex math problems, but later, I learned how difficult it was for her to apply this knowledge to solve real-life problems. After I became an engineer, I realized how difficult it was to figure out what mathematical approach you can use to solve problems. That is when math becomes exciting and fun.
Probelm understanding, looking at problem with different perspectives, and different outcomes or combos!
Stop with this bs. Math problem *are* real life problems, anyone who believes the contrary is a damn engineer!
Jk 😂
@@AliphbayIt’s like “Math ‘Street Fighter II’”!!
What I had in my curriculum was just mugging up formulas, without understanding why's and what's and the significance of the concept. I'd just mug up formulas and patterns of questions and apply the methods for such questions. Now I'm 24 and want to learn how to learn math intuitively. And my question is how'd you start from scratch?
@@gokulsrinath7714did you find the answer?
"The key to the learn anything"
Step-1 Understanding
Step-2 Remembering
Step-3 Practice
Very true, arigato
Step-4 Bread
i think you are missing the bigger picture here !
@@hunterxhunter9493 We have to go beyond the three steps to learn anything.
@@julians9070 sometimes,it is not necessary to follow these steps , but understanding the general rules ,the patterns of things around you is better , may be you have a big ammount of knowledge , but you are not that wise . that what i'm trying to say, yes you learned things you are conscious about them , but how does this affect your thinking, how can you find similar patterns in other domains etc , this is why we say a good mathematician is a good physician is because of his general understanding of things .
Math for me is the greatest endeavor of human kind. Pencil, paper, handwork, life commitment and the greatest adventure on the search of beauty.
Absolutely !
I am 71 and starting the furtherance of my math journey.
I'm so proud of you
How’s ur learning process going sir?
Syohz❤❤
As 73 year old studying math for the first time and having a mechanical background your analogy is crystal clear and very logical. Thanks for taking the time to put your thoughts on line. With the tube question I would telephone the org’s engineering section and ask them for the total length.
Best of luck
Me too. No math since college and starting again. Struggling with order of operation. My tool box is a fisher price one.
The roads probably get more use with cars than the tube and the tube requires a great deal of infrastructure restructuring to bring to fruition. I’d say the roads are produced more than the tunnels, so I’d use the miles of roads as an upper bound.
I definitely agree that learning mathematics needs a proper mindset. One just needs to understand the concepts when it comes to solving problems.
Absolutely fantastic recommendations, literally the best, I am in fact now going through these books and it's incredible how much it differs from the standard education I had
Heyyy, thanks for your comment! I’m very happy to hear that you like these references 😁 yeah, I wish I had known about them already before high school. But it’s never too late. Best of luck to you!!!
U bought them all they super expensive:/
Indeed I did buy them all. It can be expensive, especially if you don't live in the US, but if you like math, and want to get really good at it, I can highly recommend.
@@W1llbam@W1llbam Are you referring to the art of problem-solving curriculum?
@@ElijahHemingway I was referring to their books specifically such as: Introduction to geometry, introduction to algebra, introduction to number theory, and so forth and then their intermediate books as well, plus NT course. All materials are really good.
Math is actually at least two skills or disciplines. One is understanding the concepts. The other is being able to solve problems involving them. I would argue that the former is not quite as difficult in terms of sheer work required to develop as the latter. A lesson I learned much later than I would have liked to, owing to my personal history. Learned from bitter experience. Which also shows that luck counts, too. Hard work and luck are not totally independent variables. They can influence each other.
its sorta obvious' isnt it? solving probs is always the harder part
Thank you brother. I went to a rural highschool with teachers who were poor at their jobs, and therefore put me behind. Im re teaching myself math from algebra all the way up through calculus currently so i can hopefully get into school for engineering next fall. This helped tremendously
Good for you. But fair warning, the math books from “The Art of Problem Solving” are geared to train future professional mathematicians. Meaning, they attempt to teach you to think in terms of doing mathematical proofs for everything. That is fantastic but I don’t think that will make you proficient quickly enough, because it will take a couple years for you to transform your brain to think in that way.
Instead I would recommend you get two books from Saxon Publishers, by John Saxon, along with the solutions manual for each:
Advanced Mathematics, and
Saxon Calculus.
I’ll explain why I think these books will prepare you better.
Just as this video explained, normal math books teach you a new concept in one lesson (he called them “tools” in the video) and then move on to a new topic in the next lesson so you never really get to truly master the previous “tool”. The Saxon books are different than any other books I know of because the homework problems for any given lesson includes problems from the previous lessons. In other words, the problems for lesson 56 will contain problems from at least 15 previous lessons, and they will be a little harder than they were in the lesson you first learned those concepts. By the time you get to the end of the book you will be doing trig, algebra 2, pre-calculus, and calculus problems almost as automatically as if someone asked you “what’s three times two?”
The secret is to do every problem. If you get stuck, don’t waste a ton of time going trying to figure it out. Instead go to the solution manual, study the step by step solution, close it, then do the problem again, remembering each step and duplicating the solution. That method will train you in both problem solving techniques and how to think mathematically.
And while you’re at it, since you are going for engineering, get Saxon Physics too.
I promise you if you can do every problem in all three books you will crush every subject in your engineering studies.
Put you behind? Take some damn responsibly and stop being a victim.
@@ccriztoff Dude. What’s wrong with you? He’s here making conversation with the video creator, thanking him, and he’s trying to learn math on his own. But you gotta butt in to dis him - a complete stranger minding his own business?
Instead of lecturing him maybe you need to take responsibility where your parents obviously didn’t: teaching what constitutes appropriate manners and conduct.
M graduating class was 35, and teachers were hired off of how well known they were in the community rather than teaching skills
@@ATFofficial. Your class should have buck broke that teacher then 🥵
For the London Underground problem I would first of all aim for a rough ball-park figure. I'm also too lazy to take any train speeds as inputs. Looking at the Underground map, I'd like to simplify it further by imagining the network as a set of pure horizontals and verticals. The total length is then just the sum of H horizontals plus V verticals. Let's also consider the map's rectangular shape, so a horizontal is e.g. 1.25 the length of a vertical. How wide is London? Let's say 20 miles? So a horizontal is 20 miles, a vertical is 16 miles. For our "raster" Underground, let's pick 5 for the number of horizontals, and 7 for the number of verticals. Total? 5 x 20 + 7 x 16 = 212 miles. I still don't know what the true figure is, but I expect the real length to be closer to 212 than 21,2 or 2120 miles. Quick Google check.. 249 miles.
Very nice solution! 🙂
This is a basic Fermi Estimation question. I had fun making random questions up and then solving them.
Overestimated at 100,000 kms. I've got to downsize my estimate of city sizes.
Hello. I understand why a horizontal is 20 miles. It is an estimation, a proposition. I also understand why a vertical is 16 miles. Since a horizontal is 1.25 the lenght of a vertical, the vertical is 16 miles. Nevertheless, I do not understand why you have picked up 5 and 7 for the number of horizontals and verticals, respectively. Could explain it to me?
@@wilhelmjosephus4830 i suppose its just random numbers, youd get a similar no. anyway
I think intuitively understanding probability is the most useful specifically, understanding the compliments of probabilities, which is super easy honestly. Understanding the compliment of a probability will completely change your mindset when coming across a statistic.
Compliments of probability?? I totally freak out if probability. Please guide me here
@@rapoliithe didn’t mean a compliment in the sense of niceties towards probability. He meant a COMPLEMENT, which means the complementing probability to something.
You will understand immediately:
If the probability to win in your favorite game is 10%. Then the complementing probability is 90% which is the probability of loss.
Yep, this resonated with me. I did pretty average/crappy in my engineering undergrad because I didn't know how to learn. Like you said, it just felt like memorizing procedures and very little of it stuck with me in a way that could be extrapolated to novel situations. Too many concepts immediately obscured by dozens of symbols and pages of rearranging equations. That was intimidating and prevented any confidence in thinking that I was grasping any of it at all. In retrospect, after figuring out how to learn new things, the underlying concepts of the stuff that used to terrify me are embarrassingly simple to understand. I think a lot of professors are super smart in their field of study, but very little of their brain power goes to thinking about teaching and how people actually learn things. I can say that because I also had a few professors that were really good teachers and I remember everything I learned in those classes.
The key is to be humble and not be scared to afmit that you've missed a few steps during school. Start again so that you're ready to face greater challeges with the assurance that you have the necessary tools now.
@@w花b Yea, I'm good now in terms of confidence and humility. The humility has always been with me, to harmful degrees. I had to build up the ego and integrate it to some degree to come out on the other side. I had to be forced to come up with solutions on my own without me seeking direct guidance. I had to see that when I come up with solutions on my own, they are often praised by others who I regard much higher than myself. I just wonder how many people are running into psychological software limits while thinking they are running into hardware limits. Sometimes I think that psychology and philosophy should be major parts of the curriculum in any technical field of study. Not only for personal self-development, but to provide much deeper insights into the study than can be provided by technical analysis alone.
@@LCC2731 When I'm feeling overwhelmed by a technical explanation, I make sure to stop what I'm doing, and then really focus on trying to understand the simple underlying concepts. I try to build an intuition for the underlying concepts by searching for explanations written in plain English or with simple diagrams (minimal math, minimal symbols, minimal technical jargon). There's so many great/learner-friendly sources of information out there these days. And I might look at multiple sources to confirm that I am indeed on the right track in understanding the concept. Once I've gained a decent intuition, I use it as a roadmap to guide my interpretation of the mathematical formalisms that were originally overwhelming me. Knowing that I have to take the time to do this ultimately adjusts my expectations of myself to a more realistic level. A lot of feelings of frustration, intimidation, imposter syndrome are due to starting off with unrealistic expectations of yourself.
And it's easy to get frustrated if you're comparing yourself with others and how quickly they appear to "get it". But you have little idea of how much time/energy they've previously spent learning the concepts or related concepts. So even if you're exposed to the same information at the same time, those who know how to learn and those who have already put in some time to understanding will appear to be much smarter/quicker than you. I think a lot of that is an illusion. To use an engineering analogy, each of our brains have very different initial conditions (which are hidden).
Also, spend extra time on understanding fundamentals. For example, since I'm in electrical engineering, I spent some extra time understanding Maxwell's equations (there's only 4 of them) and surface charge distributions in the context of electrical circuits. Knowing how electrons fundamentally behave on a conductor, behave within electrical components, and behave with different excitations (high frequency vs. DC) allowed me to build a decent intuition that can be applied to any situation. You begin to realize most of the complexity and the conceptual breadth of your field of study comes simply from different configurations of a handful of fundamental concepts. But when starting off in a field of study, you may not understand this and it will look like everything is conceptually disconnected from itself. That's how it was for me in college. It just felt like everything was disconnected, loosely related, and as a result, very little of it stuck with me in a meaningful way. At the time, I simply learned what I needed to pass tests. I think a lot of people experience this.
Hopefully that wasn't too jumbled of a stream-of-consciousness. Just pick and choose the things that resonate with you. Sometimes it's just one or two sentences in a wall of text that really resonate with your current state of mind. Hopefully some of it helps.
Your series of comments are amazing. I'm an undergraduate math student and sometimes I feel like I've hit my limit with my grades. I need to build up my ego, understand the basic stuff and force myself to stop memorising Definitions and formulae.
Thank you for explaining in a calm and friendly way. It really makes difference in how we can view mathematics as something helpful and not just bunches of information to be decorated. Hope you can keep spreading acknowledge and helping many people like me who is trying to relearn this amazing topic. Take care x
Hey Rafaela, thanks so much for your really kind comment! I wish you best of luck with all your mathematical endeavors 🙂
Ich war auch nicht gut in Mathe, aber tada, bin ein theoretischer Physiker geworden. Ich habe erst ab der 8.Klasse gemerkt, dass wenn man sich hinsetzt und übt und übt, dann merkt man in der Klasse wie weit fortgeschritten man ist und wie sich das bemerkbar macht in Form von Lob eines Lehrers. Erst im Studium merkte ich, je mehr Mathe ich mache, desto mehr Spaß macht es. Das war davor für mich nicht so denkbar, dass das Freude in mir auslöst :).
Super dass du es wie ich gemacht hast. Ja, Übung macht wirklich den Meister. Und, wie du gesagt hast, Mathe kann wirklich Spaß machen :)
Hätte mal eine Frage:
Seitdem ich anfing mit dem Informatik Studium wollte ich meine Mathe Skills verbessern. Desto mehr ich über Mathe herausfand desto mehr wurde mir bewusst, wie wenig ich eigentlich kenne und die Themen scheinen endlos zu sein. Kommt man später an einen Punkt wo man sagen kann, nun verstehe ich alle Mathematischen Gebiete? Fühle mich so überrollt.
@@UberBossPure Eigentlich nicht ganz, aber es fällt dir viel leichter in andere Gebiete einzulesen. Die Grundmodule in der Mathematik sind wichtig und dann versteht man die fortgeschrittenen Themen besser. Vor allem in Physik, Informatik wo gewisse Ideen Konzepte uns mathematisch irgendwie bekannt vorkommen. Pure Mathe geht schon über viele Aspekte vorbei. Da gibt es mathematische Gebiete, wo sich nur ein handvoll Leute aus der ganzen Welt sich auskennen. Aber du musst für dich wissen (als Informatikstudent), was willst du später machen und welche Mathematik würde man brauchen. Für Physik viele Differentialgleichungen, riemannsche Geometrie für Allgemeine Relativitätstheorie, oder vllt Topologie für Kondensierte Materie Physik. Du musst schauen, was du brauchst und dann verwendet man die Konzepte für deine Forschung und deinen Erfolg.
@@nosferatu5500 so, master basics and you master everything?
@@WhiteStripesStripiestFan Master basics and you'll surpass those who merely memorize without understanding the advanced.
I've recently got interested in math again, and I find it amazing how it appears in many areas. There's also many solution to one problem, but I like to think with simplicity. If not only I can solve a problem, but explain it to others, then it's a simple solution. I feel like if math is taught correctly, people can see a form of beautiful art in it too. The best if you can find answers logically and intuitively as well.
I'd calculate the length as the London tube 🚂 as follows:
(Assumptions)
A1: I'd model the London city as a circle with radius r=10km (that would be my guess, i've only been to london once).
A2: And let's say we have approx. 1 station per km² (also a rough estimate :D).
(Calculation)
The area of a circle is pi * r^2 = pi * 100km² ~= 300km².
-> we have approx. 300 stations (because of A2: 1 station per km²).
Each station has 2 neighboring stations, so with the number of stations n, we have n-1 km = 299km for n=300 of tube.
Let's round that and conclude London has approx. 300km of tube if the assumptions are approximately correct.
(Solution)
I looked it up and London has 402km of tube.
That's a relative error of (402-300)/300 = 1/3 (=30%). I'm happy with that
The Tube system in London is build in a very simple fashion. There’s lines which go horizontal (east to west vice versa), lines that go vertical (north to south). All the lines kind of meet in the middle of the city (downtown). So it kind of resembles a circle. The really roughest way would be to take the area of London and pretend that it is a circle. Then calculate the diameter of that circle and multiply it by the number of tube lines there is. Kind of creating a wheel with the spines being the lines that go through the city and the outer ring of the wheel being the borders of the city.
The way I’d go about it is creating an estimating models. I’d take the width of London (roughly east acton to Stratford) and height (roughly Barnet to Mordon).
From here on out it depends on how sophisticated you want to model this problem. The simplest way would be to count the number of tube lines London has and multiply this number by the average length and width of the city.
If you want it more sophisticated you could count how many horizontal and vertical tube lines there is and multiple these amounts with the width respect length of the city.
You could also go ahead and get more sophisticated by iteratively aiming towards a more precise recreation of reality. You could model out the circle line as a the circumference of a certain diameter within this model.
To consider things like curvature of the tube lines I would just estimate a 20-30% add on top of the length and width basis we used
Hey Osman, great proposed solution! And very detailed! Let's hope this channel blows up and we get the required 100k views on this video 🙂
@@SamuelBoschMIT Danke mein Freund! Hoffe ich auch für dich. Großartige Einstellung die du hast. Vielleicht läuft man sich ja irgendwann über den Weg. Bewege mich auch in der Finanzbranche
I enjoyed reading this very much. I’m a programmer that at age 40 nearly just got into math (because of computer science stuff and general interest)
You have any books you’d recommend for folks wanting to start over and build up
Finding the length of the London Tube system involves measuring the total length of all the individual subway lines. The London Underground consists of several lines, each with its own length. The best mathematical solution would be to add up the lengths of all the individual lines to determine the total length of the entire system.
Obtain the length of each subway line: Research or use official sources to find the length of each individual line in kilometers or miles.
Sum up the lengths: Add the lengths of all the lines together to get the total length of the London Tube system.
Total Length
=
Length of Line 1
+
Length of Line 2
+
…
+
Length of Line N
Total Length=Length of Line 1+Length of Line 2+…+Length of Line N
Could have condenced that to "find the length of all them on Google and add them up" 😂
I have naturally learned these skills over the past year or so in my persuit of a maths degree. Although I personally found it much easier to find these skills by basically being talented at mathematics, lowering the time it took for me to completely understand and gain new tools. Like a 60 unit hour course in linear algebra was completely sufficient for me to understand most all of the material, from the most basic applications of matrices to vector spaces and eigenvalues. All the fun stuff which would normally be too quick for most people to pick up, I simply applied myself for hours on end and learned the material effectively. That’s kind of what this video describes, it just says “learn it and then you’ll know it” circumventing the fact that plenty of people are just genuinely bad at math, because they have a low aptitude for abstract reasoning in general. Perhaps I’m being too negative but this approach hand waves away the biggest problem of natural ability, and people struggle with math despite spending time to learn the concepts because they don’t have that aptitude.
>That’s kind of what this video describes, it just says “learn it and then you’ll know it” circumventing the fact that plenty of people are just genuinely bad at math, because they have a low aptitude for abstract reasoning in general.
Hello, Rigo. Yes, the video in question did not address the lack of abstraction. However, it is important to note that abstract reasoning is a skill (not a fixed genetic trait) that can be trained, developed, and refined. The key to achieving success in mathematics lies in identifying the right approach. Therefore, the use of the term "aptitude" is not entirely appropriate in this context. In reality, almost anyone can acquire proficiency in mathematics, and topics such as Linear Algebra and Analysis are often considered basic, trivial and straightforward within the higher-level mathematical community (no offense). With that said, the reasons for individuals failing to achieve success in these subjects are typically related to other factors such as laziness, lack of discipline, inadequate education systems, cognitive biases including anxiety, imposter syndrome, constant comparison to others, or aversion, insufficient motivation (worth noting that there are relevant studies on the subject, such as hypofrontality, ADHD, behavioral addictions (which are increasingly prevalent in our modern society), etc.), flawed learning methodologies, knowledge gaps, lack of interest, unrealistic expectations, or an unsupportive environment. Additionally, in a world where computers and machines can automatically solve problems, there is a tendency towards complacency among many individuals, leading to a reluctance to engage with concepts that machines can easily process in a fraction of a second. Studies have been conducted on this phenomenon, known as "Google Syndrome," which can also be applied to other fields. Neurology did also shed light on these issues.
_Perhaps I’m being too negative but this approach hand waves away the biggest problem of natural ability, and people struggle with math despite spending time to learn the concepts because they don’t have that aptitude_
Your statement may create the impression that this issue applies to the majority of people, while this is not the case at all. There are certainly rare cases of individuals with severe mental handicaps who may face significant challenges in mastering mathematical concepts. However, these individuals often struggle with communication, basic conceptual understanding, and other fundamental skills that can make learning mathematics difficult. In any case, it is unlikely that such individuals would pursue higher education, so they do not represent the "average" student population. The video in question is addressing the average Joe or Jane, and it is reasonable to suggest that such individuals are certainly capable of grasping concepts in linear algebra and analysis, provided that they approach the material correctly.
_[...]and people struggle with math despite spending time to learn the concepts because they don’t have that aptitude_
Once again, this assertion of yours is, for the most people, incorrect. In fact, aptitude is often the least consequential factor, the least of the problems in explaining why individuals struggle in mathematics. Rather, the primary factors that account for failures in these subjects are often more complex, including behavioral addictions, such as those involving pornography, social media, or being chronically online in general, and the tendency towards instant gratification that characterizes a major part of our modern society. These behavioral addictions have been shown to contribute to hypofrontality, which can have profound effects on the brain's reward system, and thus, necessarily on the ability to learn, to concentrate, to abstract reasoning, etc. People didn't believe this at first, and since it is so prevalent nowadays, because people are "used to it", they don't even notice the consequences arising from this.
In the past year, these concerns have received official recognition, with the International Classification of Diseases, Eleventh Revision (ICD-11) formally recognizing compulsive sexual behavior disorder (CSBD) (Remember: People laughed about this, admittingly because certain religious sects use the empirically verified unhealthy nature of pron addiction to further their cause of religious living). The negative impact of such behavioral addictions on learning is then often compounded by the pace of modern life, which emphasizes speed and immediacy over deliberation and depth of understanding. In the past (say the 50s), individuals who wished to research a question or topic were required to visit a library and sift through multiple books, which encouraged thorough reflection and deeper engagement with the material or think about it entirely themselves without assistance.
By contrast, in today's world, people are often satisfied with minimalist, on-point and immediate answers that require little effort or time investment (just look at this video or other video essays and for the comments that "summarized" this long video and then see how this summary often misses the in-depth idea of what the video is trying to say, but people still being satisfied and thanking them "for saving them 30 minutes" => Necessity for fast answers, symptomes of impatience, etc), which can lead to factual knowledge without a more profound understanding (which is why I have a personal dislike of "fact checkers" that even more so encourage this behavior). This minimalist attitude and lack of attention span can also be observed in the popularity of platforms like "UA-cam Shorts" and "TikTok" compared to longer video content that is often skipped. Admittingly, the average person has less free time to devote to a particular subject nowadays, making it more challenging to engage with complex material fully in length. In other words, this modern trend towards instant gratification has become so pervasive that individuals who reject this approach are still often forced to conform to it. People *still* (despite the vast amount of research in neurology and existing brain scans) underestimate how severely the age of the Internet influenced and still influences our brains.
Therefore, average individuals who might have succeeded in the 60s with linear algebra and analysis may struggle in the present due to the constraints imposed by modern society, Internet and educational systems. The introduction of the Bologna Process and the adoption of bachelor's and master's degrees in Europe and Germany have resulted in the boiling down and confinement of knowledge into shorter time frames, making it more challenging for average individuals to engage with material comprehensively, therefore ultimately elitizing academies for the few talents who can keep up with the modern pace. In contrast, in the past, diploma programs allowed for more extended periods of learning, which facilitated deeper engagement with the material, allowing even the average Joe to confidently get a degree without being a fast-learning genius.
@@Kaje_ Are there amazing books, spectacular tutoring programs and other wonderful resources you'd like to recommend that can enable one to master the fundamentals of math?
I am a student taking a course specifically to become an engineer, but sadly am poor in my maths but still am going to make my dream come true by understanding, remembering and practicing 😊
Math is easy, pro tip; multiplication is just addition. Division is just subtraction.
This is absolutely terrific. I believe that this could crack the code with public schooling in general. Couldn't it be explained that the height of education is intuition? Intuition being the accumulation of knowledge, wisdom and creativity. I'd love to have a real discussion on this because we must know how to develop our intuition if we hope to progress as a species. Unfortunately, the modern school system has failed us.. math was never explained to me in this way and I struggled.... But now, all of a sudden, math is being explained in an intuitive sense and it's clicking with me. Now let's try and translate intuition to the other academic pillars. This is just so incredible!
Beautiful insight, and I totally agree with you @David Walker 👏🏾 I think math, like a lot of other subjects, can be cultivating as a natural part of understanding the world - it’s even, in fact, touted as the first natural science. As intuitive and creative as we can be, I think everyone has the potential and capacity to do math - math, as universal as it is, is not reserved for some exclusive club. I enjoy fostering the math intuition within every student I work with as a math tutor. ☺️
It's surprising how powerful ratio is, I could solve most of my high school level problems with it.
Danke für das Video, hole mir nun auch die Bücher! Hab geliked und kommentiert damit der Algorithmus dein Video hoch pushed
Suuuuuuuperrrrr!!!!!! 😁💪💪💪💪 Viel Erfolg wünsche ich dir dabei!
You have a talent for making complicated topics accessible!
Great video, Samuel! As someone who studies math, I totally agree with the mindset-part. But a lot of time it's not even a person's fault but the fault of their teachers/parents etc. who tell them that "math just isn't for them" really early on (or even worse, there are teachers saying "math isn't for girls" which just excludes half of the population).. One of my friends at uni told me that some of his teachers in elementary school said the same thing to him but he was lucky to have a physics-teacher in 6th grade who really encouraged him to understand physics and math and in the last few years of school he even went on to win some national & international math-competetions.
For the tube-problem my thought would have been the following: I know that Berlin has a diameter of roughly 40 km with a population of around 4 million. I also know that London's population is around 9-10 million (let's just assume 10) and that London's population density should be a bit higher (I would have guessed by 20%) since Berlin is really spaced out. So London_Pop/Berlin_Pop = 2.5 and London_Dens/Berlin_Dens = 1.2 which means that London_Area/Berlin_Area = 25/12; therefore Londons diameter should be sqrt(25/12) which is close to sqrt(2) which is close to 1.4 times the diameter of Berlin, so around 56km. I would also expect that the tube does not go to the edges of the city as a tube system is usually built for the parts closer to the city center so I would subtract 10 km from the city's diameter to get the tube-system's diameter. (This would be around 46km now) I also know that Berlin has 3 lines which, kind of, cross the whole city (so their length would be close to the diameter of the tube-system) and another 5 which only cross half the city. I would just double those amounts because, while London's population is 2.5 times the population of Berlin, I also think that London's tubes have a slightly higher frequency than Berlin's so that makes up for that. With all these assumptions I would therefore arrive at 6*46 + 10*23 = 506km. This certainly isn't the best guess but it works without knowledge of any city's rail-length.
Hey Leo, thanks for the comment and sorry for my slow reply! Yes, I completely agree! It’s so easy for a teacher to discourage someone from going in a certain direction, but so difficult to motivate people to do so. Especially the example you just mentioned
Also, good job with the estimation process - I really like your answer! 🙂
If a teacher tells girls that maths is for boys. Tell the teacher to look up the name Ada Lovelace then ask if they still think their statement holds true!
About the math isn't for girls , girls are all on onlyfans nowadays...
My dad and I would try to learn math when I was little and it never worked out. I guess I always wanted to do something else or he wasn’t great at teaching it. So basically throughout my schooling and as I was going into collage he would say but you can’t do the math and I decided against classes with math or even trying a class with math. Now I graduated and thinking back that I could have done the math and not I’m stuck doing something I’m not that interested in. I had one small math class when I was at college and came out top of the class of 14 students. Not huge it was simple math but I realized I could do math.
For the tube problem, i took a fairly simple approach. I once took the track from Heathrow to downtown which took around 1 hour (on average it seems airports take a rough 1 hour by transit). Assuming an average speed of 40km/hour this would be around 40km of track. I know that line extends beyond my stop so just guessing that that line is 60km long. Starting from there, I remember 8-10 colors on the subway map which indicates around 10 lines. Now I’m guessing heathrow line is one of the longer ones so let’s say the average line is around 40km, times 10 lines gives us 400km of total line. Now tunnels are generally underground in the city and overground in the suburbs, I’m guessing central London is about 40km in diameter while the total tube coverage area stretches 80km in diameter. Thus Longer lines are primarily overground but more sparse while shorter lines are primarily underground but more frequent. These effects should mostly cancel each other out so around 40-50% of the total line should be tunnelled which gives a range between 160-200km!
Your brilliance, dedication and enthusiasm are shown in your work. Keep on doing great jobs for everyone, you're a legend
Thank you so much 😀
My lecturer of physics used to tell us that there are 3 stage of learning a certain topic in this ascending order.
1. Understanding
2. Telling
3. Writing
Total length of the london tube tunnels, multiple approaches:
1. GoogleFu - this information is probably available as a statistic on the internet = 249 miles
2. Map (Paper of Digital) - Assuming tunnels are relatively straight between stations, measure the straight-line-distance between each tube station, for every line, sum this all up and add 10% as error
3. Tube Timetable - will show average transit time between stations. Some of this time is speed up, max speed, slow down, stop at station. Lookup exact distances between a subset of stations, and generate an approximate formular for transit-time vs distance on different lines. Then apply this to the entire timetable.
Issues:
- There is probably some missing information related to disbanded tunnels, ancient unused stations, and tunnels to non-public train depots. This might requires adding on a percentage as an error factor.
- Question specifically said "tunnels" and not all the tube is "underground". Google maps might be able to show you where lines switch to being above ground.
After studying Algebra, geometry, trigonometry and statistics., proceed to number theory, vector calculus and abstract algebra. Lambda calculus can be used in computer programming.., matlab.., binary it's awesome! Mathematics is the language of everything! 🎧🎶🤩
The radius of greater London is about 45 miles. This makes the circumference about 270 miles. Imagine each tube running from the center out 45 miles to the urban perimeter. You need enough tubes so that one need not walk too far to get to a tube station, so guess about 4.5 miles between end stations on these radially arranged tubes. Each tube is thus 9 miles apart at the perimeter. But nearer the center you don’t need as many, so the number is cut in half every 9 miles. So there are 9x30 + 9x15 + 9x7.5 + 9x3.75 + 9x2 or rounding to 9 x 57 = 513 miles of tubes.
Here are a few strategies that might help you learn to understand math more intuitively:
Start with the basics: Make sure you have a strong foundation in the basic concepts and principles of math before moving on to more advanced topics. This will help you better understand the more complex ideas that come later.
Practice regularly: The more you practice solving math problems, the more intuitive your understanding of the subject will become. Try to work through as many different types of problems as you can, and don't be afraid to make mistakes - it's all part of the learning process.
Use visual aids: Diagrams, graphs, and other visual aids can be very helpful in understanding math concepts. Try drawing pictures or diagrams to represent the problems you're working on. This can help you see the relationships between different concepts more clearly.
Work with others: Collaborating with others can be a great way to improve your understanding of math. You can bounce ideas off each other, explain concepts to one another, and work through problems together.
Experiment with different approaches: There may be multiple ways to solve a math problem, and trying different approaches can help you find the one that makes the most sense to you. Don't be afraid to think outside the box and try something new.
Seek help when you need it: If you're struggling with a particular concept or problem, don't be afraid to ask for help. You can ask your teacher or tutor for clarification, or seek help from online resources or study groups.
This is literally written by chatGPT
For the benefit of others interested, let me share two obvious titles as a first read.
1. A Primer for Mathematics Competitions by Zawaira & Hitchcock
(A recent Googling pops up a couple of similar titles but I am unfamiliar with those.)
2. The Art and Craft of Problem Solving by Paul Zeitz
Excellent! Thank you Sheldon! 🙂
This was a fun problem, I've been seriously studying mathematical fundamentals since the start of the year.
I imagined London as a circle with radius 10mi. I cut the circle into 8ths with 4 lines, and I cut it again into an arithmetic series of circles from 2 miles to 10 miles. Then you just sum up everything, 60•pi mi + 80mi = 268.4 mi. I looked up the actual number and saw 250mi online.
Anyways I hope my math checks out, but I was happy to get the right solution. A few months ago I wouldn't know where to start :).
hey what do you mean by cutting it into arithmetic series of circles?? I don't really understand the wording lol......
Your analogy on the tooltips was really interesting and helpful, thanks a lot!
You’re very welcome :)
Sweat the small stuff, and never be afraid to go back to basics.
As Tobias Dantzig wrote in his book 'Number : The Language of Science ( which I highly recommend ) : ' Why is it that only mathematical processes can lend to observation, experiment, and speculation that precision, that conciseness, that solid certainty which the exact sciences demand ? When we analyze these mathematical processes we find that they rest on the two concepts : number and function ; that function itself can in the ultimate be reduced to number ; that the general concept of number rests in turn on the properties we ascribe to the natural sequence : one, two, three'.
I see London as a circle with diameter of 25 miles. I take the center as hotspot which most of the railways crosses. Then I take 8 lines through the center point (like a pizza with 8 pieces) since I would build a railway in a city this way since the density of the traffic is and should be more center focused. Additionally I put 1/4 (7,5 miles) of the diameter in the middle of every piece on the outside since in the outer regions are connected to weak since with further distance from the center railway connection gets separated to far with too big radius. So I come to a result of 8x 25 miles + 8x 5 miles = 240 miles
Great solution!
My solution to the tube problem:
The tube trains average speed is 33Km/hr. Find the total time it takes for each train to travel it’s entire line and add them together, formatted as a decimal of hours. Then multiply that value by the average speed (33) to get an average of the total distance of the tube line.
You always make learning feel so clear!
The problem with School and college tuition is that its a factory. You are sorted into your supposed intelligence then you get trapped there. Depending on what conveyer you are on you will only be given the course material to satisfy a pass for your stream. Everything is pace and grades, the actual knowledge gained doesn't really matter. The big problem is that textbooks also follow this as well, the books just target the exams or levels to be studied. Continuity which is so important doesn't seem to exist. This of course is partly due to the physical size of a book. In the UK it was very hard to learn advanced shool maths as they all jumped in at more difficult areas without the all important lead up. I found American text books so much better and I only wish I could have obtained them when I was younger, (pre Internet).
Ich habe für mich gemerkt, dass das Anwenden das Beste ist. Wenn man viele Aufgaben löst dann prägt sich dass besser ein als das Script mit den Beweisen ins Hirn zu stopfen. In den Aufgaben hat man auch viele Fallbeispiele und wenn man etwas ähnliches kennt, weiß man vielleicht wie man das lösen muss. Außerdem ist die Feynmanntechnik auch sehr empfehlenswert.
Heyyyyoooo Nosferatu, danke für den Kommentar 😉 jaaa, Feynmantechnik ist super. Leider musste ich auch so viel auswendig lernen im Studium. I’m gymnasium war es viel besser
For the tunnel problem solving I will check the radius of London. I will calculate the length of a line using the assumption that it crosses the whole city usually lines make , then I will count number of lines and I'll multiple the length of a line with the number of lines ,and if I have a map of the tunnels maybe will give them some 5 -10 % bonus because metro trains don't go always in a straight line , that's my 4 grade math solution 🤣
I think that we gain intuition (a feeling how to solve the problem) when we do some memorable examples (about some physics; a different way of doing the geometry) and reconnect the idea using space repetition (explaining to a 5yo).
And not doing a bunch of exercises in a day; maybe that after you have understanding and test your new tool set.
Interconnecting ideas related to different subject with wide scope (hate when say I leave that to your physics teacher or that is part you will see in probability), not isolated pure math.
I kind get some of that on edX.
take hillingdon as "x" and havering as "y"
Take into consideration of all the routes from x to y from the tunnels london's public transport system.
find the length of each route.
and lastly add them all up to find the total length of all the tunnels.
thank you
In my secondary and high school I absolutely hated mathematics but recently when I understood the reasons behind the formula and standard forms, my interest in mathematics bloomed! Can someone help me find the resource to understand mathematics better? Thank you mate for the resources and video!!
The Khan Academy is a great resource!
@@Shannon_Robbie Thanks!
I’ve always been amazing at math. I’ve always understood it intuitively. Its why I love it.
Check out my new video about math skills you ACTUALLY need in life 🙂 ua-cam.com/video/A5CMAcyI42o/v-deo.html
@@chugwhanio9538 Hahhahah I'm not sure what point you're getting at? :)
Very difficult with ADHD and mindset😐😐
Use the scale given on the map to measure the separare lengths by a ruler or a measuring instrument. Do the conversion for each and total the individual results for each to determine the actual length of the tube.
the way i would estimate the length is first thinking about the size of London. London as a circle should roughly have a diameter of 40 km. Since the density of the tunnels should be higher in the center of the city i thought of a tunnel strucuture similar to a star (first draw two straight tunnels across london that look like crosshairs then add another two tunnels splitting every quarter of the circle(London) so that london looks like a pizza, and then another four tunnels that split every eighth of London.) That makes 8 tunnels with a length of the diameter of London which is 40 km which results to a total length of 8 * 40km = 320km
Very interesting solution! Yeah, I never even thought about this. But of course, the tunnels should be structured in a certain (logical) way, so this is a very smart estimate 🙂
I appreciate how you explain things so thoroughly!
to solve the 'tube' problem i would first know the total height of the tunnels and the length and the would use the formula of curved surface area of a cylinder by breaking it down and then would add all of it to get the area the reason why I chose curved surface area is because he asked the area through which the train goes but not how much can he put into the tunnel.If i am still wrong correct because i tried my best :))
i dont think people thoroughly understand math, they just do what they know as right. for example, i didnt understand how fractions with different denominators were added, i just did what i knew as right. now i know why it works.
I don't know why this vid just pop up to my feeds but honestly you have the looks that compliment your intellegence😁👍🏻
Hahahhah thanks you 😊
I love the series "Everything you need to learn in a simgle fatbook" and the series "Fundamentos da Matemática Elementar". The FME can teach you from the basics in math (from probability) to some things more complex (like introduction to calculus). The geometry books, for example, have 1400 geometry problems (really). It has 11 books, but only in portuguese language
About the problem you mentioned, we can just calculate the length of all subway trips in one direction
Ich finde die Gesamtfläche von London heraus (1.572km^2).
Ich Male ein Rechteck auf ein Blatt Papier und nehme an das das Rechteck London ist. Den Rechteck gebe ich die Fläche von London.
Ich nehme die Wurzel von der Fläche von London um die Seitenlänge des Rechteckes rauszufinden.
Ich behaupte das ein gutes U-Bahn-System so lange sein sollte das man mit der U-Bahn zu allen Ecken des Rechteckes kommen kann und zu den jeweiligen mitten fahren kann. ( Wie eine art Spinnennetz). Um die Diagonalen zu berechnen benutze ich das Werkzeug der Satz des Pythagoras. A^2+B^2=C^2.
Ich rechne alle langen zusammen und multipliziere das Ergebnis mit zwei weil die U-Bahn in beide Richtungen fährt.
Hier die Rechnung:
√1572=39.648
=40
√40^2+40^2 =56.568
=57
(2×40+2×57)×2=388
=388
=388 Kilometer Tunnel länge
Weil es in der Stadt Mitte vielleicht noch mehr Tunnel gibt kann man wahlweise noch 1 diagonale hinzufügen.
Wobei man dann auf 445 Kilometer kommt.
Coole Lösung 🙂
400 miles without looking anything up. But I am a Londoner. So I know there are twelve or so tube lines. Diameter of London about 20 miles. 12 times 20 is 240. But some of the lines run above ground. So call it 200 miles. It is 400 miles if you mean the total length of tunnels in both directions. (When I looked it up, I found that 55% of the system runs above ground, so that was the major error I made.)
As I am reading through different solutions to the problem, people are not actually solving the problem, they are estimating the answer. This is something that is mostly lacking in math education. In any important problem, three steps should be taken: 1. Estimating the answer, 2. Solving for the answer, and 3. Checking the answer.
Exactly! :)
My answer is to figure out how fast the train goes which should be common knowledge of the train company (mph if your in America like me, or km per hour) then ride the train to see how long it takes to go from station to station. Don’t count time between stations as they are not part of the tunnel system anyway. I’m not sure how the stations are set up, but you should be able to use all of this information to calculate roughly the length of the entire tunnel system.
For the problem, I would take out my phone and then search google. This is the best way because it has a high chance of being accurate, and I would likely solve this question in under ten seconds and get it right.
That doesn’t count though hahahahahah
A concise introduction to pure mathematics
I know London is approximately 20miles Nth-Sth by 30miles East-West. I know the main lines and their very approximate layout e.g. Central Line runs East-West: therefore ~30miles. I add up all the lines and this gives me a total length of ~150+ miles. I did this mentally in ~5mins and used my fingers to add the lines (in multiples of 10miles).
i live in paris so im gonna base my answer on the paris subway : i know there are 15 lines, each line has approximately 17 stops and it takes approximately 1min 30 to get to one stop. so in total there are approximately 1245 subway stops in paris, the subway moves at approximately 60km/h so it means appropriately 1,5km per station so 1245 x 1,5 = 1873km
A typical city maybe has about 8 subway lines, each one of those taking about an hour if you ride them from one end to the other. I'd say the average speed of a subway train is 40 km/h, so that gives you roughly 320 km in total.
Thank you for your inspirational message and friendly presentation. I'm already in my 40's but I hope by picking up the textbook you recommended, and doing some of the problems in the book and online, I can refresh some knowledge and learn new ideas!
I would have nailed that interview question 😂 I just saw your instagram video and I was luckily correct even though my guess was very simple. I just estimated that the main part of london is within a 20x20km square and I wanted to calculate the length of the lines of a grid within that square. So I thought a tunnel every 1km would be too close so I went with every 2km. Therefore I summed up 10 vertical tunnels with 20km length with 10 horizontal tunnels with 20km length and thats exactly 400km. I was very surprised when I saw the true answer 😂
Very nice 😊
I just thought another solution for "The Tube" problem. I'll just look for 50-100 cities which resemble the population density of London and then take out the mean of the underground tunnels. Obviously I consider that the length of underground tunnels in these cities are known to me. And geographic factors will too deviate the mean length but still it will be a good estimate. The more cities I consider, more will be the accuracy...
For the amount of track: What I know : Taking the Thames river from the middle of London to where it opens up to the ocean is about 30 miles, and takes about 4 hrs. The city thins out about an hour into that trip. All this rest is pure guess: Maybe London is roughly a circle 15mi in diameter, packed with people. Population doesn't matter because the tunnels were dug long ago with much smaller population. it's coverage in area that matters, it has to be a short walk to a station from anywhere in that area. 1 mile of track per square mile of area keeps a walk under 10min. The area in square miles of London, plus 10 spokes from center to edge to facilitate cross town travel... the 10 spokes (radius is 7.5 miles) equal 75 miles +area pi x 7.5²miles ≈ 250.5 miles ≈ 403km of track?
Nice!
Okay, we need basic tool, lots practice, take new tool, lots practise again, use it to simplified for anvanced math problem.
2:50 tools for
Lots and lots of practice
Use simple tools of hammer and.
Memorize steps to solve a problem. Good memorizes. For every new tool, we practice 50times.
Simple toolbox
Concise introduction to mathematics
"Young man, in mathematics you don't understand things. You just get used to them." -- John von Neumann
I took advantage and I am taking advantage of doing well with your books thank you
That’s great!!!
I don’t know if this is the okay way to do it and I think I’m late for this but personally I would get a map of the London tube. Let’s say a 1:1000 scale. I would then at the center of every track, put a line from the beginning to the end, then measure it up and do the conversion back
There is time where the tube goes right or left and not straight, that’s why I would put the line in the center, in order to get more straight line sas possible. Otherwise I should measure the angles.
i have always had good grades all throughout school,i could solve problems on paper with understanding & some meorization too. but i have realized i always lacked application of math which is why i i didnt develop love for it . Time to give math another chance & enough time
Amazing video, another one. So I think it's not my discipline but I'm highly impressed by this skills. Great work.
I see forward to a video about your fitness routine! Keep going, it's great!
Heyyy Lucas, thanks for the comment and sorry for my slow reply! Yes, I would he happy to make such a video. Probably this summer already :)
I just have to find a way of making it fit the main topic of this channel, given that I’m not running a fitness channel 😉
aint no way this man casually just threw out, "for every 1 hour of learning, spend 20 to 100 times it on practicing"
Thank you. I'll follow this
This content really enhanced my understanding!
the tube problem answer is the (square root of the area of the london township) times (up line + down line 5+5)
considering the circular area to project as square on the topology of earth.
this was awesome!
london is similar in size to kolkata, so square root of 1600 sqkm is 40km approx.
So, 40km * (5+5) up and down lines = 400km tube lines
thanks man for the opportunity you are cool
Nice! 🙂
Heabby Na! But most of our Math teachers suck.
For context I do not know anything from the London subway system and I’m at 9th grade level mathematics.
I would look at it from a top down aproach in a 2D space because even if subways change elevation the values in any meaningful way. And I would add all of the values together. But to be more precise with this I would find the area of intersections if there is any. And I would subtract it from the final value.
This video is such a gold nugget in the whole "math" youtube content! Maybe it's not a unique idea for the video but with such a elegant execution!
Also sorry for my English, overall very positive about this type of content!
Hmm… to solve the problem, we’d need to define tunnels and what constitutes the tube. Let’s say that tunnels are the enclosed areas trains go through.
We want to find total length traverseable by train.
We know… not much…
But cutting up a diagram of the subway routes, calculating the time it took on someone’s commute from a point on the line to their station and knowing the speed of the train could help us find the length of that section. We could then take the map and cut the tunnel segments into equal lengths and then calculate the length
by hand, but that would take too long
Very mildy differently, we could do the same thing, but then lay them in rows such that a sort of square is formed where one side is length of tunnels and the other is the quantity of them and find the area.
Assuming no vents in the tunnels, we could try to pump it full of fog, and then see how much volume is used to fill the tunnels and then divide the volume used by the average cross sectional area of the tunnel to find total length
We could try riding all the tunnels,
We could ask repairmen or managers how long the tunnels are
Or we could use good old google to solve the problem
Or ask the interviewer “what’s that?”
I’m not even sure my answers that good, I don’t know what we’re even given XD
Thanks man I'm improving slowly and slowly I hope I'll countinue like this your really helped me thanks sir
You're very welcome 🙂
Well, first, we need to estimate the entire surface area of London. Which is 20 miles long by 16 miles wide. So we do 20 × 16, which is 320 miles. Then we find just the length of one tube tunnel. Which in order to do? That's we need to measure the length of a platform on one of them and keep adding its length until we reach the end. I'm just gonna make one assumption here and say it's about 10 miles long. Finally we can take our surface area of London which is 320 miles subtracted by the length of one tube tunnel, which is 10 miles. The answer to that will be 310 miles. I don't know if this is the correct answer, but I tried my best.
Edit: I have a much better solution. Do what I kinda did there but instead of getting the surface area. Let's actually just get the length and width London. Which again is 16 by 20 miles. Let's take the average length of the tube tunnel which I estimated to be 10 miles. Let's estimate the lengths of the tunnel system with the width of the tunnel system. First, we take 16 − 10, which is about 6 miles. Now let's take 20-16, which is about 10 miles. Now let's take the length times with to get the surface area, which is 6x10 is 60.
This video helped me understand the topic much better!
Well, here's my estimate of London's undeground:
1.1)It would be nice how big London is. Idk how big it is, but let's say it is a circle with diameter equal to the length of my city(which is long and thin, and is almost certainly smaller in area than London, so that sounds about right)
1.2) Idk how big my city is either, but i once saw in navigator app that my daily commute(almost the entire length of it) would take about 4 hours on foot.
1.3) Idk how fast humans walk, but i remember seeing that kerbals(which are smaller than humans) in the video game KSP run at 1 m/s exactly, so let's assume that's also true about human walking speed.
4 hours * 1 m/s = 14 400 m, which is about 14.5 km.
2.1) It would be nice to know how many lines there are in the London tube system. I know there is a YT Map Men song that consists of all their names(Or was it stations!? Well, whatver, it's probably close enough). I don't remember how many there are, but it was probably about 100s long.
2.2) I remember the random estimate that saying "mississippi" takes 1 second, so probably same for line/station names.
That means there are 100 lines.
3) We know that London's diameter is (exactly!) 14400 meters, but how long is a line on average? Well we can assume they are straight lines, going between two random points in a circle. Which is something i could probably calculate, but that's a horrible estimate anyway, so i really don't care. Also they are not straight... so let's just say they are around 2/3 of the diameter, meaning our lines are 10km on average
4) 100\*10km = 1 000 000m. Which is my final answer.
5) Pray it's the correct order of magnitude.
Super Video! Habe dich bei Niklas Steenfatt und David Döbele gesehen haha :) Ich hoffe es kommen mehr solcher Videos
Danke für den netten Kommentar! Kommt mehr 🙂
You give me hope for myself. I’m always down on my ability. Thank you so much
😊
I would use a square or rectangle and estimate length and width, such as 20 by 30. I would then assume there is some pattern to the tube system for it to make sense to riders, such as an array/grid and thus estimate somewhere around 400 to 500 miles, or 640 to 800 km. The problem is I have no reference for how big London actually is but I know Toronto is about 45 km across so would make an assumption that since Engand is a smaller country, London might also be smaller. Therefore I might say that a reasonable answer is 640 to 700 km.
Did he say 15k a month for an internship? What?
The most important mathematical tool I've _ever_ come across, is the lowly percentage calculation. Armed with it, you'll gain an entirely new and useful understanding of the world. But... By gaining that knowledge, and using it in practise, I sadly also found out how few others employ it daily, such as professed "experts" even within medicine and economics.
I think one other way to tackle the Tube problem is by using statistics (or statistical software). Its a little bit of a cheat, but we can make some assumptions about London, if we know some numbers and how it compares to other cities. We can assume, that given the expense of underground rail, underground rail systems are correlated to the population density of a city, because economically it only makes sense to build one if enough people are using (and paying for) it. Second, we have to assume that London is not "special" in any way and city planers more or less use the same metrics and assumptions used by city planers in other big cities. With this, we can search for other cities that have roughly similar metrics like population densities, have a big population, can actually afford to build them (so only big cities in middle/upper income countries), circular shape etc. Then we can use statistical software to let the computer calculate the size of the average rail network adjusted for population size, lets say km/ per million inhabitant as our dependent variable, and things like population, population density, GDP per capita, proportion of suburbs to city center and the radius of a roughly circular city. Should give us a pretty good estimate, although that would kinda be cheating because we are not doing a back of the envelope calculation. Plus point: You can actually give them a confidence interval down to an exact decimal place.
INteresting approach! 🙂
Why doesn't this guy have 1 million subscribers? So underrated.
Hahhahah that’s what I’ve been asking myself too 😂 Thank you!
Answer : we can run a train through all the tracks from start to end and then subtract the pre-covered distance(need to be recorded) from the new distance on the odometer .
Hmmm interesting solution - although I don’t really get how this helps you estimate the total length without actually running this experiment :)
Damn bro you’re ripped. Good shit!
Hahhahah that's 🙂
1 Mindset
2 Practice
-Get a few tools and hone your skills with those tools
1 hour learning a tool=20-100 hours practice
-Get a new tool only needed
That’s exactly right :)
Am glad to hear this
Additional notes:
1. Read the book "How to Solve It" by G. Polya.
2. The biggest thing is to do lots of problems. Finding and joining Art of Problem Solving is basically 85% of the battle.
3. Use the Moore method for learning mathematics. This is a method of reading where you prove every theorem a book provides without reading the proof first. This can be extremely challenging if not impossible (depending on the book), but its' the best way to learn a mathematical subject.
4. Variant on 3, once you prove it your way, have a peek at the book's proof. If it differs from your's, try not to read the entire proof. Try to prove it another way. This will help you look at the same subject from different perspectives.
5. All books on how to solve things, are marginal at best. The best way to learn to solve, is to solve problems on your own. Struggle, and when you are about to give up, continue. It took me over a year to prove Morley's Theorem. I spent an 1-2 hours each day trying to solve it. I eventually got it. That is the level dedication and effort you will need.
6. Apply the Moore method to a book like Geometry For College Students by Isaacs, or Geometry Revisited. Lots of practice thinking out of the box can be had by applying the Moore Method to a good geometry book.
7. Memorize theorems and results after you have a good understanding of them. Yes, that's right memorize. That is what they do in French schools and per capita, France wins the most Fields Medals. If you don't have basic theorems and results at your finger tip, you cannot hope to tackle complex problems when you need to identify a useful theorem to use. Appreciate that you can never understand anything fully. You can only deepen what you know.
Good luck.
Thanks Samuel for this video. Im from Unfortunatelly in my country my teachers don't taught me how to learn. I have finally exam for 1 year. Im close to finish mid School (it is before study in Poland ) and it would be nice to write it good. I also want to learn maths because I want to be a professional trader in future.
You can do it! Best of luck! 🙂
To solve the tube problem, first I would buy the longest tape measure I could find. Then I would fly to London and walk along each tube measuring as much as I could and marking it down. After that I would add up all the measurements and then use my phone to look up the correct answer because I would definitely be wrong.