@@ajcongdon1772 The way you are getting steamed up about other people's mild comments sounds like a cardiac arrest waiting to happen. Just chill and stop fighting the world. You'll be the better person for it. Just take some deep breaths and let it go. Breathe in.....and out; breathe in.....and out. Feeling better? It's not all about you A J. Just chill!
Sorry, but there is really no need to take up so much time introducing yourself on every single video. None of the other maths tutors on you tube do so. It is really so very tedious.We know who you are. TabletClass Math is sufficient identification.
@@AlexZander688 Yes. and I do fast forward past that. But it's irritating all th same. As is the whole presentation to be honest. Why are you sticking your oar in anyway? Are you his dad?
@@djcl1538 I gave it a go because I love learning about maths. But I got really bored with the repeated self-inroductions, and long-winded presentation style. I'm sure he is a nice man, but I get much more pleasure and learning from other channels. I would add that I am far from the only commenter who has criticised his tedious long-windedness, yet he has not changed it. As for you, you just come across as rude and ignorant. So get knotted.
@@djcl1538 I'M confused? ME? First you characterise my reply as nonsense. You add that I am 'confused' and subject to fits of irrational pique. And between those statements you state that you sense that I am a nice man and polite. You do not give reasons for any of your statements, whereas I gave reasons for all of mine. You clearly have nothing of value to say. Go to the bottom of the class. If I ever meet you I'll knock you for six!
Hahaha I am so embarrassed how I totally forgot my percentage and I graduated from penn state from 86 to 90. With a master degree in case management. Shaking my head .I am now a subscriber to the fullest. Thank you🤣👍🏻
I believe I learned the "cross multiply" technique for solving this, which creates two equal fractions, 15 over 100 and 7 over some unknown number designated as "x". Therefore we need to solve for x in the following equation: 15/100 = 7/x. Cross multiplying these two fractions gives you 15x = 700, which simplifies to x = 700/15 or x = 46.66 repeating.
The method I learned is a bit longer, but easier for me. 15/100 = 7/x. Then 15x = 700. Then x = 700/15. Then x= 46.67. My method is such that I can do the math in my head without the need for a calculator.
All numbers have patterns 1 is 15% of 6.666 repeating 2 is 10.333 3 is 20. That's it . The pattern starts over. So 20 +20 is 40 think 6. plus 1 so 40.666. if you know the pattern you don't even have to do the math.
Many ways to do it but the least path of resistance I decided to take was; Covert .15 to .10 by multiplying it by 2/3. Then you must do the same to 7 and you get 4.666 Now you have a new question that says: “4.666 is 10% of” So just multiply both by 10 and you get 46.666 as your result.
I agree that you set up equations; and that verbal phrases are important. You mentioned that ‘is’ means equal. But you never mentioned that ‘of’ means multiply. I set up the equation this way: 7 = 15% x N 7/.15 = N N = 46.66 = 46.67 I do enjoy your videos. 🙂
Base=percentage/rate Percentage =base x rate Rate=percentage/base I’m a 60 year old Catholic school graduate who never forgets what was beaten into him.
Not sure where "90" came from. Formula I was taught was 7=.15(x) where x is the unknown number/variable. Then you divide both sides of equation by .15, which makes 7/.15=× then x=46.67 (rounded up). Easy peasy.
There is(much) easier way to calculate that , you even dont need on smaller numbers calculate & calculator or paper&pencil!!you just divide 100:15 = 6,6666666 and then multiples with 7 and you get this result too and same thing is with any other percentage number
@@veljkovidanovic4204 ne, 100 označava maximalni postotak zato je 100!! recimo da je on rekao o 12 od 24% opet bi bilo isto jer 100:24 i dobiš 4,1666 i pomnožiš sa 12 i to je 50 a 24% od toga je 12
@@Mr11ESSE111 brate 46.666666 je broj od koga ti je 15 posto 7 sto znaci da 7 puta 100 je 700 i podeljeno sa 15 46.666666 tako da ovo je najlaksi nacin
Logically, this is a simple equation x * (15/100) = 7 and you have to divide 7 by (15/100) to find the number x. In the end 700/15 = 46.66. I'm amazed at all the "formulas" shown here when it's so simple, but most of them are also correct.
I love this guy, but some teachers need to do less 'explaining' and concentrate on more commonsensical methods of communicating the facts of the mission. For instance, I work in construction and I was able to solve this mathematical equation in about 2 seconds. How? Exactly the same way all you did. I just did 7 divide by 15% and arrive at the long 46.666 number. I would've rounded the number up the next value to 46.7 but that's just me. Check the math, 46.7 x 15% = 7.005. Then tried 46.6 x 15% and got 6.99. I still thought rounding it up to 46.7 was correct. But I thought I was wrong. So I had to spend over 12 (very long) minutes to learn I had it correct the whole time! My ADD brain can't handle the scenic route of arriving at the answer to a math problem. I get the concept training and all, but sometimes a person working out in the field just needs to solve a math problem quick.
I was taught 7/15 X 100=46.6666... (or 46.67) and 15% of 46.6 is 15 X 46.6/100 = 6.99 or ~7 (You can almost do this on your fingers). This way you don't have to move the decimal and get it in the wrong place or make it more complicated than it is (x=?). I graduated college in mid 70's with a Bachelor of Science. It involved a lot of math. Latter in life when I got married and had high school age children and I couldn't help them. I could get the correct answer in the back of the book but they would tell me "Dad, you didn't do it right".
Learned similarly to you. Quick mind calculations as I was taught. 15% = 7; 1% = 7 ÷15; 100% = 7 ÷ 15 × 100 = 46.7 Rounded to 47 Sometimes teaching 'modern' can be necessarily complicated.
I failed math in high school because I refused to write everything I did in my head down. Once I even got accused of cheating because I aced a test and finished it really really fast. I was on lsd but I don't think that qualifies as cheating. She didn't know I was on lsd but she was mad anyway. I hated school.
I learned it this way. 7 is 15% of the total (100%). So you divide 7 into 15 pieces which is .4666. So we know that 1 piece (1%) is worth .4666. Take the .4666 times 100 pieces to find out the whole.number. .466 x 100 = 46.66
I would always teach children that find maths hard to find out what 1%is, then if they couldn’t go any further at least they had accomplished something. If they could continually find 1% of any number I gave them then some of them could progress to the next step.
Maybe, your long lecture before the problem is solved is losing your audience. I just went on and tried to solve the problem myself. The answer is 47. The bell is getting ready to ring for the next class. Students are tuned out. Just a joke. You did good Sir!
great video. May I say in a kind spirit that it would set a good example to try not to say prom instead of problem? No offense intended. Kids face so many challenges in learning today.
Did it in my head first, by realizing, yes, it's 7/0.15. So, how many times does 0.15 go into 7? 0.15 goes into 1.5 ten times, 4 times 1.5 = 6, So the answer is 40, plus how many times 0.15 goes into 1. Well, if 0.15 goes into 1.5 ten times, then it goes into 1 two thirds of ten times. Two third of 10 = 6.666... So the answer is 46 and two thirds.
I appreciate what you say in your preamble, but maybe you can tell everyone what time cue to go to in order to get to the heart of the issue. I don't have the patience to listen to useless information.
14 minutes & 36 seconds to explain this??: Pain in the ass! If people have time to waste... then you MIGHT want to watch this video. But you've been warned!
If you are going to use a calculator, it is easy. When I first saw the problem I saw it as a mental arithmetic problem. In mental arithmetic, get rid of the decimals. So rather than 7/.15, try 700/15 and the answer comes easily as 46.666... Again 13.5 is 15% of what number becomes 1350/15 = 90. Calculators have almost destroyed mental arithmetic but it is still fun.
First off, you have to understand that out of 100 parts of the Main number, 15 of those parts, add up to 7. So, Divide 7 into 15 parts or (7/15), which will help you to determine the quantity in a single part or a unit part.... So, 100 times of that quantity will give you the Main number.
The way my 9th-grade algebra teacher - shout-out to Mr. Pearce, who taught at Redford High in Detroit way back when - explained these kinds of problems to us, “is” means “equals” and “of” means “times” in this case. Also, you move the decimal 2 places to the left for the percentage number to work out the equation. So you would rewrite the problem as: 7 = .15x 15 is the same as 15. and that becomes .15 to figure out a percentage problem. And “.15x” means “.15 times x, which is the unknown number you’re trying to find. Again, you now have 7 = .15x and if you divide both sides of the equal sign by .15, you’ll be left with a certain number = x, and the problem will be solved. 7 ÷ .15 ≈ 46.67 because the 6 after the decimal is a repeating decimal.
I remember that to create an equation from words you must use the keywords. Always of was division and is for the answer, and times equal’s multiply. Back in grade school we weren’t allowed to use a calculator. To further solve the equation you had to use long division. 7 divided by .15 =700 divided by 15 = 46.6
I wholeheartedly agree. Most of the problem I've seen people have with "percents" has nothing to do with percentage, and everything to do with word problems in general. The most important keywords are: "is" or "has" can be replaced with "=". "of" or "at" can be replaced with "x". "per" can be replaced with "/". "and" (where it's not just being used to separate multiple equations) can be replaced with "+". "more than" can be replaced with "+". "less than" can usually be replaced with "-", BUT this one is tricky because "a is 1 less than b" really means a = b - 1, NOT 1 - b, so you have to swap the two things that follow it. "%" can be replaced by moving the decimal point two places to the left. "what" is usually the quantity that we are solving for. This covers at least 80% (um, I mean, 80 out of 100?) of math problems expressed in words. Oh yeah, I missed that one: "out of" also means "/". This all seems obvious, but that "less than" thing fools a LOT of people, as does the fact that "and" can mean addition, but it can also mean that we're dealing with more than one equation. The give-away here is that if you see more than one "is", you're dealing with more than one equation. So the original quesion, "7 is 15% of what number?" becomes 7 = .15 x N Since we're solving for N, all we have to do is get everything else on the other side of the "=", which in this case means to divide both sides by .15, and we're there.: 7 / .15 = N Keep in mind that algebra was invented to make it easy to move things from one side of the equation to the other side - this problem would not be presented until the students are ready for dealing with variables as placeholders. I'm sure you already know all of this, but to me it's criminal that they don't actually TEACH these things. They just expect kids to figure them out by guessing and error. Which doesn't work. It just comes out as "you are stupid, because you don't know these things we haven't taught you." Naw, no axe to grind, here.
An elementary school textbook I used described three types of percent problems: A is B% of C (A) Percent of a number (B) Finding what percent one number is of another (C) Finding a number when a percent of it is known
As a retired teacher, whenever I introduced a new subject in Math, I spend the first day going over the vocabulary of that subject. Half of most standardized tests are word problems and while many can do the math, they avoid the word problems which is confusing- they don't understand the vocabulary.
And this is the thing that almost NO elementary teachers teach. And since the language is fundamental to ALL math, they produce students who think math is too hard, and they are just stupid. Stupid teachers have probably been the cause of more crime and misery than mean parents.
I used Parentheses to stop confusion of X and x. Use simple portions 7:15::X:100 15X=7(100) Both 15 & 100 are %…so forget division of both sides by 100. (7)(100)/15=46.666667 = 46 and 2/3 Answer in decimal and fraction Check answer… 15% of 46.666667 is 7. It works for 46 2/3 also.
7 is 15% of.... ??? Just roughing the problem in my head, I came up with a number between 44 and 45. Like : 44.3333333333~, or, 44 and one-third? If 7=15%, then 14=30% (doubled). 30 is 1-third of 90%, so 14x3=42, and 42=90%... that leaves 10% to account for... 10% is 2/3 of 15%, so divide 7 by 3 which = 2.333~, which = 1/3, but we need 2/3, to make up that last 10%, so double that 2.3 for a value of 4.6. Add it to the 90% (42) : 42+4.6 = 46.6 Turns out the correct answer was in fact 46.6... Yay. My convoluted way (as opposed to the simpler, cleaner algebra method) still got me there. In all honesty, I forgot to double the 1/3 value (2.3) at the end so I came up with 44.3 for an answer and seeing the answer was actually 46.6 made me recheck my math, and that's when I noticed the 2.3 discrepancy was due to forgetting to double the 1/3 of 7 to get the 2/3 required (10/15%) to round out the 100% calculation. I'm probably pissing off so many mathematicians right now. LOL.
I don't remember what I learned so I just made an equation. I know percentages can be expressed as numerals by moving the decimal point 2 spaces left and I know 50% of 4 is 2 or .5 x 4=2. Make 4 the unknown and you have .5x=2. So this is .15x=7 or 7/.15=x so x=46 2/3. Seems easy.
7 divided by .15 to check your answer - THE MOST IMPORTANT PART OF THE PROBLEM - Which you did not show -to check the answer - (now I know why our children learn nothing in school) -
Making myself watch your video was a little like taking some foul-tasting medicine. I didn't want to do it, but it did make me feel better. Doing any kind of math has always been like being lost in a foreign country to me. But I must say you do a good job of explaining, and I will look for your videos. Thanks a million.
This is a fine example of why I am not an engineer. I can't do algebra or much other than simple math. I got 52.5. I did it in my simple' quick figuring a percentage in my head ' method of thinking that if it were 10% then it would be 70 and if it were 20% it would be 35 and figured it to be in between 35 and 70 but it just doesn't work out that way. That's why I'm just a welder and mechanic.
For fun, I frequently take 5-10 seconds to solve the problem taken from the picture of the video. I would have used 600 instead of 700 as the denominator of the problem.
I like your videos, but they would be way better without all the self promotion upfront. Save it for the end. Also, the more correct answer is 46 2/3. (Or 46.7)
Say you have 8% sale tax where you live. You buy something for $20. How much sales tax did you pay? 8 X 20 / 100 =1.6 or $1.60. Total cost $21.60. No x's needed.
Why does this guy keep popping up at the op of my UA-cam screens? I'm into math and arithmetic and puzzles and stuff and would be interested if someone has a creative approach to doing and teaching it, but a guy who's going to take 14-and-a-half minutes to explain a creative way to figure out what number 7 is 15% of? Sorry, I'm not watching. I calculated it in my head as 7/.15 which is equal to 700/15 which is equal to 1400/30 or 140/3. And I got 46 and 2/3.
Not understanding the given answer. If you intend to limit the answer to one decimal place then the answer is 46.7 Two decimal places is 46.67 Three decimal places is 46.667 46.6 is incorrect.
H’mmmm Na! What age group are you identifying with? 4 minutes in, still no progress on the problem! And then you start talking about calculators!? WTF? What The Facts! You got a calculator on your shoulders ....Brain....that’s what we should elect to use when solving on the run % challenges! Such as in a store or in conversation....Now show them (Us) how to use our god given calculator....You reminded me about being in school decades ago, and nothing seems to have improved! Regards to your effort, but not good enough for my five year old! Who is in the 21st Century “Mental arithmetic” denial!
I earned a handful of stars... but didn't do the problem as you. I simply made 15% into a fraction 15/100 and made an equivalent fraction... 7/x so 7/x = 15/100 cross multiply and divide .... so 7*100 = 15x 700 = 15x ... 700/15 = 15x/15 .... 46.666... = x I used equivalent fractions to solve the problem. It is so easy. You don't need an example and then apply the example. You just need to know that 15% is 15 of 100 and you want to know the denominator that goes with 7 to make a pair of equivalent fractions to 15/100.
7 is 15% of what number I will try before watching the video.. 7 is = 15% of what number = 15/100(x) 7 = 15/100 x 7/1=15/100x 100*7=15x 700=15x x=700/15 x=46.67
Actually I solved this in my head without all the hoops. I asked what percent of 100 is 15... thats pretty easy 6 15's is 90 leaving 10 which is obviously 2/3rds of 15 thus 6.66 is the percentage that 15 is to 100... then simply multiply 7 times 6.6 six times seven is 42... 2/3rds of 7 is 4.6 there's your answer 46.6 no pencil required.
Greetings. The answer can be determined by assuming that the number is X. Now 15% of X = 7, and 3X=7×20. That is 3X=140 and X=140/3 =46.6 recurring, rounded to 46.7. The number is 46.7.
If 7 is 15% of a number then 7/15 is 1% and 700/15 is 100% = 46.67. What's the mystery? It took about a second to work that out so why is the video almost 15 minutes long, especially as I only needed 0.114% of the length of the video to come to the same conclusion? This video makes me glad I left school at 15
I just watched this video. I understand that you want to teach a particular lesson here, but I have a question. Isn't this particular problem solveable in an easier and still correct way? I mean if you know that 7 is 15% of x, then you also know that 1% of x is 1/15 of 7. So if you divide 7 by 15 and multiply the answer by 100, you get the value of x. I realize there are multiple ways to solving problems, it just seemed to make sense to me, to do it the shortest way. I love your channel, the problems help stimulate my aging mind. :)
Way too much jaw time. Teach students to speak math. “7 is 15% of what” “is” means equals “%” means hundredths “of” means times Translation: “7 = 15/100 • n” or “7 = .15 • n”
This video lasts for 14.6 minutes. 468884 people have watched it so far. (466884 x 14.6 ) /(60 x 24 x 365 ) > 13 You have wasted more than 13 years worth of people's time on this utterly trivial problem
decimals are inadequate for expressing the solution to this problem: if 7 is 15%, then one third of this is 5%. 7 divided by three is two and a third. Double this and you have 10% of the total - 4 and two thirds. Multiply this by 10, you have 100% of the amount. 4 x 10 = 40 and two thirds x 10 = 20 thirds. Twenty thirds is 6 and two thirds, so 46 and two thirds is the most accurate expression of the full amount :)
Why not just jump to the basic equation that comes down to this: 0.15X = 7 X = 7/0.15 therefore X = 46.7 You also go on and on with stories that have nothing to do with learning math, and examples that just leads one astray.
I am a probuct of the California special education I had a really hard time with all the subjects in school and somehow graduated in 1987 ... usually having a really hard time with handling a job for very long just because I am always feeling like I am at the bottom of the employment totompole never able to move up right now working at Goodwill 4 some 4 years of doing the same duties over and over ... keep feeling if I understand math a little better maybe my life would be better..not dumb or a crackhead no criminal history it's just at 54 most of the time I feel Iam still that kid floating though high school back in 1987 ..from Ventura high school now live in Klamath falls Oregon,. keeps feeling if I understand math and computers couldn't understand what x and y was on a graph calculate .try hard not to be sick or late for work just at Goodwill the will never move me up watching a lot of people come and go Goodwill is one of those jobs is just really hard to get a head . I will talk alot about pie R square...and I don't know what else I can do at 50 something..or if I have to start over at a new job I have to start at the bottom a long with all the other high school kids .. thanks for your time you and listen good night from Klamath falls Oregon
you got to 5 minutes and then I gave up when you went wandering off again. what you should do, in my opinion, is put the answer up front and then piece by piece explain why it is the answer. Something after the style of: if 7 is 15% then 1% is 7/15 and 100% would be 100 x that. Write that out in numbers or something. Go on from there. This is simply obfuscation by preamble and anecdote.
I pity those adults who can't estimate this in their head in a few seconds. My brain came up with something around 45. Calculator was 46.666. 7 divided by .15. Cripes.
I’ve watched a handful of your videos because you’re doing exactly the questions I’m currently interested in. But every video I’ve watched is about 90 or more percent chat and a tiny bit of time addressing the math problem which represents my only motive for watching. I’m going to try to avoid any more of your videos.
In my head I did 7 is 15% so 14 is 30%, so 14/3 is 10%. 14/3 is 4 and 2/3 or 4.66 which, x 10, is 46.6 No calculator, just old school common sense really.
Convert % percent to decimal equivalent. 15% = 0.15. Then divide 7 by 0.15 (7/.15), which is 46.667. 14.667 times 0 .15 (15 %) So 46.667 times 15% (0.15) = 7. Instead of 15%, use 50%. If 7 is 50% (1/2) of some number, then the number is 14.
You totally lost me on your 2nd line. 14.667 time 0.15 = 2.20005. What does that have to do with the problem? And what does this thing with 50% have to do with the problem?
what a load of malarky. 1% of the unknown number is 7 divided by 15 the number is now the answer to the above multiplied by 100. 46.6 no wonder people are so poor at maths
I thank you very much for the time you spent putting together with William comments below. I wish you went straight to the issue; to solve the problem w/o so much jargon. Try to make it straight up, without so many other examples of other percentages and what have you. You seem to drift off the point.
Long minutes of blablabla, for nothing. I'm not a mathematician and i resolved this problem in a few seconds. Sorry for my incorrect english, i'm french.
OK...2 minutes into the video and this guy is just yammering on and on and not showing how to work the problem but selling hisself! Yo dude...give us a timeline so we don't have to listen to all your bull!
Instead of a damned lecture, divide 7 by .15 (15%) and the answer is about 47.
Instructor talks to much
@@ajcongdon1772 If you skip to the interesting part, you have to ignore ninety percent of the video altogether.
@@ajcongdon1772 The way you are getting steamed up about other people's mild comments sounds like a cardiac arrest waiting to happen. Just chill and stop fighting the world. You'll be the better person for it. Just take some deep breaths and let it go. Breathe in.....and out; breathe in.....and out. Feeling better? It's not all about you A J. Just chill!
46.6666
Maybe he is trying to explain it for the 1st time to a bunch of 6th graders?
Sorry, but there is really no need to take up so much time introducing yourself on every single video. None of the other maths tutors on you tube do so. It is really so very tedious.We know who you are. TabletClass Math is sufficient identification.
Very easy to fast forward past that.
@@AlexZander688 Yes. and I do fast forward past that. But it's irritating all th same. As is the whole presentation to be honest. Why are you sticking your oar in anyway? Are you his dad?
@@djcl1538 I gave it a go because I love learning about maths. But I got really bored with the repeated self-inroductions, and long-winded presentation style. I'm sure he is a nice man, but I get much more pleasure and learning from other channels.
I would add that I am far from the only commenter who has criticised his tedious long-windedness, yet he has not changed it. As for you, you just come across as rude and ignorant. So get knotted.
@@djcl1538 I'M confused? ME? First you characterise my reply as nonsense. You add that I am 'confused' and subject to fits of irrational pique. And between those statements you state that you sense that I am a nice man and polite. You do not give reasons for any of your statements, whereas I gave reasons for all of mine. You clearly have nothing of value to say. Go to the bottom of the class. If I ever meet you I'll knock you for six!
@@djcl1538 Yawn!
Hahaha I am so embarrassed how I totally forgot my percentage and I graduated from penn state from 86 to 90. With a master degree in case management. Shaking my head .I am now a subscriber to the fullest. Thank you🤣👍🏻
15% is 15/100. So…
15/100 = 7/x. Cross multiply and divide.
(7•100) / 15.
700/15 = 46.67
Thanks! That took a lot less time than 14:36.
I did it the proportion way too. Way faster
And you understand the principle behind the equation and can use it whatever the unknown is.
(7/x)=(15/100)
(7/x)=(3/20)
3x=140
x=46.667... ✓
Simple, isn't it?
I believe I learned the "cross multiply" technique for solving this, which creates two equal fractions, 15 over 100 and 7 over some unknown number designated as "x". Therefore
we need to solve for x in the following equation: 15/100 = 7/x. Cross multiplying these two fractions gives you 15x = 700, which simplifies to x = 700/15
or x = 46.66 repeating.
Correct, same here !
Same.
Answer is 46.67
This is the way I learned! It never fails me.
105
The method I learned is a bit longer, but easier for me. 15/100 = 7/x. Then 15x = 700. Then x = 700/15. Then x= 46.67. My method is such that I can do the math in my head without the need for a calculator.
Just do 7/15 and multiply by 100
Easy method. Not longer at all
All numbers have patterns 1 is 15% of 6.666 repeating 2 is 10.333 3 is 20. That's it . The pattern starts over. So 20 +20 is 40 think 6. plus 1 so 40.666. if you know the pattern you don't even have to do the math.
There's a simpler n easier way to solve.... 10% is 4.66, therefore 100% is 46.6 (answer)
You did it easier.. Thank you
7=.15N
Divide each side by .15
Ans. = 46.6
Many ways to do it but the least path of resistance I decided to take was;
Covert .15 to .10 by multiplying it by 2/3.
Then you must do the same to 7 and you get 4.666
Now you have a new question that says:
“4.666 is 10% of”
So just multiply both by 10 and you get 46.666 as your result.
I agree that you set up equations; and that verbal phrases are important.
You mentioned that ‘is’ means equal. But you never mentioned that ‘of’ means multiply.
I set up the equation this way:
7 = 15% x N
7/.15 = N
N = 46.66 = 46.67
I do enjoy your videos. 🙂
Yeah, this is always how I taught my 4th and 5th grade students.
From Steve. I AGREE TO AGREE 👍.
We taught proportion to kids in the form of: "is" over "of" = "percent " over 100 (part/whole). 7/x = 15/100. Thanks for the shortcut!
A percent is simply 1/100. So 100 percent = 100/100 = 1 (the total). No big deal.
Base=percentage/rate
Percentage =base x rate
Rate=percentage/base
I’m a 60 year old Catholic school graduate who never forgets what was beaten into him.
Not sure where "90" came from. Formula I was taught was 7=.15(x) where x is the unknown number/variable. Then you divide both sides of equation by .15, which makes 7/.15=× then x=46.67 (rounded up). Easy peasy.
Sorry,you didn't show how we received the answer :90" to start off with i want to know
That is how i calculated it too, but I haven’t watched the video yet, so I will see what he has to say about 90.
Can’t be 90. 10% of 90 is 9 So 15% is 13.5. 46.67 is bingo
The 90 is the solution for another problem. Though I don't fully blame you for being so inattentive with how unnecessarily long this video is.
46.66👍
JUST LIKE MOST MATH TEACHERS.YOU LOVE TO HEAR YOURSELF TALK BUT SAY VERY LITTLE
TO HELP...
Is over of
7/15= 46.67
In other words 7 divided by 15
“Is” over “of”.
Or how to explain a ridiculous easy problem so confusing. Well done
Well said! Best laugh in a long time. Thanks, still laughing...
AND, work a couple of unrelated ads in in the process 😆
😀😀
There is(much) easier way to calculate that , you even dont need on smaller numbers calculate & calculator or paper&pencil!!you just divide 100:15 = 6,6666666 and then multiples with 7 and you get this result too and same thing is with any other percentage number
Or just 700:15
@@veljkovidanovic4204 ne, 100 označava maximalni postotak zato je 100!! recimo da je on rekao o 12 od 24% opet bi bilo isto jer 100:24 i dobiš 4,1666 i pomnožiš sa 12 i to je 50 a 24% od toga je 12
46.66
@@MuhammadJaved-sr8rx where
@@Mr11ESSE111 brate 46.666666 je broj od koga ti je 15 posto 7 sto znaci da 7 puta 100 je 700 i podeljeno sa 15 46.666666 tako da ovo je najlaksi nacin
7 / 0.15 - why is that so hard such that it needs a 15 minute video?
Looooooooooong winded infomercial. Yawn.
Did it in my head.
One third of 140 ...
( yes, I'm well aware I'm weird )
No, you're not the one who's weird...😉
Logically, this is a simple equation x * (15/100) = 7 and you have to divide 7 by (15/100) to find the number x. In the end 700/15 = 46.66. I'm amazed at all the "formulas" shown here when it's so simple, but most of them are also correct.
I love this guy, but some teachers need to do less 'explaining' and concentrate on more commonsensical methods of communicating the facts of the mission. For instance, I work in construction and I was able to solve this mathematical equation in about 2 seconds. How? Exactly the same way all you did. I just did 7 divide by 15% and arrive at the long 46.666 number. I would've rounded the number up the next value to 46.7 but that's just me. Check the math, 46.7 x 15% = 7.005. Then tried 46.6 x 15% and got 6.99. I still thought rounding it up to 46.7 was correct. But I thought I was wrong. So I had to spend over 12 (very long) minutes to learn I had it correct the whole time! My ADD brain can't handle the scenic route of arriving at the answer to a math problem. I get the concept training and all, but sometimes a person working out in the field just needs to solve a math problem quick.
I was taught 7/15 X 100=46.6666... (or 46.67) and 15% of 46.6 is 15 X 46.6/100 = 6.99 or ~7 (You can almost do this on your fingers). This way you don't have to move the decimal and get it in the wrong place or make it more complicated than it is (x=?). I graduated college in mid 70's with a Bachelor of Science. It involved a lot of math. Latter in life when I got married and had high school age children and I couldn't help them. I could get the correct answer in the back of the book but they would tell me "Dad, you didn't do it right".
Learned similarly to you. Quick mind calculations as I was taught.
15% = 7;
1% = 7 ÷15;
100% = 7 ÷ 15 × 100 = 46.7
Rounded to 47
Sometimes teaching 'modern' can be necessarily complicated.
That's right.. They just try to make the problem complicated for our. Kids
I failed math in high school because I refused to write everything I did in my head down. Once I even got accused of cheating because I aced a test and finished it really really fast. I was on lsd but I don't think that qualifies as cheating. She didn't know I was on lsd but she was mad anyway. I hated school.
I learned it this way. 7 is 15% of the total (100%). So you divide 7 into 15 pieces which is .4666. So we know that 1 piece (1%) is worth .4666. Take the .4666 times 100 pieces to find out the whole.number. .466 x 100 = 46.66
This would appear complicated to many people. I would just divide 7 by 15 and multiply by 100. Quicker and easier by far!
Yes, or as I did it 100/15 then 7x the result which is the same thing really...
I would always teach children that find maths hard to find out what 1%is, then if they couldn’t go any further at least they had accomplished something. If they could continually find 1% of any number I gave them then some of them could progress to the next step.
Maybe, your long lecture before the problem is solved is losing your audience. I just went on and tried to solve the problem myself. The answer is 47. The bell is getting ready to ring for the next class. Students are tuned out. Just a joke. You did good Sir!
great video. May I say in a kind spirit that it would set a good example to try not to say prom instead of problem? No offense intended. Kids face so many challenges in learning today.
Jeeez. 14 minute commercial for yourself to solve a problem that a tik tok teen could do in 30 seconds
Did it in my head first, by realizing, yes, it's 7/0.15. So, how many times does 0.15 go into 7? 0.15 goes into 1.5 ten times, 4 times 1.5 = 6, So the answer is 40, plus how many times 0.15 goes into 1. Well, if 0.15 goes into 1.5 ten times, then it goes into 1 two thirds of ten times. Two third of 10 = 6.666... So the answer is 46 and two thirds.
I divided the 7 by three and multiplied by 20.
don't encourage anyone to "plug the arithmetic into your calculator" they need basic skills FIRST!
I appreciate what you say in your preamble, but maybe you can tell everyone what time cue to go to in order to get to the heart of the issue. I don't have the patience to listen to useless information.
SUCH A VERY PRIMARY SUBJECT! IS THAT WHAT YOU ONLY KNOW? IT'S SO SIMPLE MAN! NO NEED TO TRY!
This method got me interested in math to the point of completing all math up through Differential Equations with an A.
14 minutes & 36 seconds to explain this??: Pain in the ass! If people have time to waste... then you MIGHT want to watch this video. But you've been warned!
@@djcl1538 Sorry. I can't possibly help you out. I must confess I lost patience at some point and stopped watching.
If you are going to use a calculator, it is easy. When I first saw the problem I saw it as a mental arithmetic problem. In mental arithmetic, get rid of the decimals. So rather than 7/.15, try 700/15 and the answer comes easily as 46.666... Again 13.5 is 15% of what number becomes 1350/15 = 90. Calculators have almost destroyed mental arithmetic but it is still fun.
I'm in left field. I was thinking 7 is 10% of 70 and 35 is half of 70 so m 105 ?
..or starting with 15%, work out what you need to do to get 100%. Divide by 3 then x by 20. So, answer 7 x 20 / 3 = 140/3
7 / 15 x 100 = 46,6, homie you’re wasting time.
I was taught to use the P=BR method of finding percentages and it stood for P= part, B= base and R= rate.
Man,you talk too much for nothing.to 5he point ,pls.
First off, you have to understand that out of 100 parts of the Main number, 15 of those parts, add up to 7. So, Divide 7 into 15 parts or (7/15), which will help you to determine the quantity in a single part or a unit part.... So, 100 times of that quantity will give you the Main number.
The way my 9th-grade algebra teacher - shout-out to Mr. Pearce, who taught at Redford High in Detroit way back when - explained these kinds of problems to us, “is” means “equals” and “of” means “times” in this case. Also, you move the decimal 2 places to the left for the percentage number to work out the equation.
So you would rewrite the problem as:
7 = .15x
15 is the same as 15. and that becomes .15 to figure out a percentage problem. And “.15x” means “.15 times x, which is the unknown number you’re trying to find.
Again, you now have 7 = .15x and if you divide both sides of the equal sign by .15, you’ll be left with a certain number = x, and the problem will be solved.
7 ÷ .15 ≈ 46.67 because the 6 after the decimal is a repeating decimal.
Are you after his job?
Mathematics is the programming language of the Universe
7*100) /15 is the most simplst way rather than going with (.) Valued especially on division
7 divided by .15 is answer
rule of 3: 15% is 15/100, so 100 x 7 : 15 = 46.666666
I remember that to create an equation from words you must use the keywords. Always of was division and is for the answer, and times equal’s multiply. Back in grade school we weren’t allowed to use a calculator. To further solve the equation you had to use long division. 7 divided by .15 =700 divided by 15 = 46.6
I wholeheartedly agree. Most of the problem I've seen people have with "percents" has nothing to do with percentage, and everything to do with word problems in general. The most important keywords are:
"is" or "has" can be replaced with "=".
"of" or "at" can be replaced with "x".
"per" can be replaced with "/".
"and" (where it's not just being used to separate multiple equations) can be replaced with "+".
"more than" can be replaced with "+".
"less than" can usually be replaced with "-", BUT this one is tricky because "a is 1 less than b" really means a = b - 1, NOT 1 - b, so you have to swap the two things that follow it.
"%" can be replaced by moving the decimal point two places to the left.
"what" is usually the quantity that we are solving for.
This covers at least 80% (um, I mean, 80 out of 100?) of math problems expressed in words.
Oh yeah, I missed that one: "out of" also means "/".
This all seems obvious, but that "less than" thing fools a LOT of people, as does the fact that "and" can mean addition, but it can also mean that we're dealing with more than one equation. The give-away here is that if you see more than one "is", you're dealing with more than one equation.
So the original quesion, "7 is 15% of what number?"
becomes 7 = .15 x N
Since we're solving for N, all we have to do is get everything else on the other side of the "=", which in this case means to divide both sides by .15, and we're there.: 7 / .15 = N
Keep in mind that algebra was invented to make it easy to move things from one side of the equation to the other side - this problem would not be presented until the students are ready for dealing with variables as placeholders.
I'm sure you already know all of this, but to me it's criminal that they don't actually TEACH these things. They just expect kids to figure them out by guessing and error. Which doesn't work. It just comes out as "you are stupid, because you don't know these things we haven't taught you."
Naw, no axe to grind, here.
An elementary school textbook I used described three types of percent problems:
A is B% of C
(A) Percent of a number
(B) Finding what percent one number is of another
(C) Finding a number when a percent of it is known
As a retired teacher, whenever I introduced a new subject in Math, I spend the first day going over the vocabulary of that subject. Half of most standardized tests are word problems and while many can do the math, they avoid the word problems which is confusing- they don't understand the vocabulary.
And this is the thing that almost NO elementary teachers teach. And since the language is fundamental to ALL math, they produce students who think math is too hard, and they are just stupid. Stupid teachers have probably been the cause of more crime and misery than mean parents.
Isn't the purpose of the test to see if you know both? What good is math without being able to apply it to situations?
Divide 7 by 15 and multiply 100
I used Parentheses to stop confusion of X and x.
Use simple portions
7:15::X:100
15X=7(100)
Both 15 & 100 are %…so forget division of both sides by 100.
(7)(100)/15=46.666667 = 46 and 2/3
Answer in decimal and fraction
Check answer… 15% of 46.666667 is 7. It works for 46 2/3 also.
7 is 15% of.... ???
Just roughing the problem in my head, I came up with a number between 44 and 45. Like : 44.3333333333~, or, 44 and one-third?
If 7=15%, then 14=30% (doubled). 30 is 1-third of 90%, so 14x3=42, and 42=90%... that leaves 10% to account for... 10% is 2/3 of 15%, so divide 7 by 3 which = 2.333~, which = 1/3, but we need 2/3, to make up that last 10%, so double that 2.3 for a value of 4.6. Add it to the 90% (42) : 42+4.6 = 46.6
Turns out the correct answer was in fact 46.6...
Yay. My convoluted way (as opposed to the simpler, cleaner algebra method) still got me there.
In all honesty, I forgot to double the 1/3 value (2.3) at the end so I came up with 44.3 for an answer and seeing the answer was actually 46.6 made me recheck my math, and that's when I noticed the 2.3 discrepancy was due to forgetting to double the 1/3 of 7 to get the 2/3 required (10/15%) to round out the 100% calculation.
I'm probably pissing off so many mathematicians right now. LOL.
I don't remember what I learned so I just made an equation. I know percentages can be expressed as numerals by moving the decimal point 2 spaces left and I know 50% of 4 is 2 or .5 x 4=2. Make 4 the unknown and you have .5x=2. So this is .15x=7 or 7/.15=x so x=46 2/3. Seems easy.
7 divided by .15 to check your answer - THE MOST IMPORTANT PART OF THE PROBLEM - Which you did not show -to check the answer - (now I know why our children learn nothing in school) -
Making myself watch your video was a little like taking some foul-tasting medicine. I didn't want to do it, but it did make me feel better. Doing any kind of math has always been like being lost in a foreign country to me. But I must say you do a good job of explaining, and I will look for your videos. Thanks a million.
This is a fine example of why I am not an engineer. I can't do algebra or much other than simple math.
I got 52.5. I did it in my simple' quick figuring a percentage in my head ' method of thinking that if it were 10% then it would be 70 and if it were 20% it would be 35 and figured it to be in between 35 and 70 but it just doesn't work out that way.
That's why I'm just a welder and mechanic.
I usually approach this question as 100÷15=.6.66... x 7 = 46.66...
For fun, I frequently take 5-10 seconds to solve the problem taken from the picture of the video. I would have used 600 instead of 700 as the denominator of the problem.
I like your videos, but they would be way better without all the self promotion upfront. Save it for the end. Also, the more correct answer is 46 2/3. (Or 46.7)
Say you have 8% sale tax where you live. You buy something for $20. How much sales tax did you pay? 8 X 20 / 100 =1.6 or $1.60. Total cost $21.60. No x's needed.
That is a different problem altogether. The base is already known, which is why there is no need for variables.
Geeeez....You sure went about it the hard way.
Divide 7 by 100. Multiply that # by 15.
DONE.
!
Better answer is 140/3.
If 7=15%? What number is it?
(7÷15)=0.46 (15%÷15%)=1%
0.46×100%=46.66...
It is☝️ correct.
Why does this guy keep popping up at the op of my UA-cam screens?
I'm into math and arithmetic and puzzles and stuff and would be interested if someone has a creative approach to doing and teaching it, but a guy who's going to take 14-and-a-half minutes to explain a creative way to figure out what number 7 is 15% of? Sorry, I'm not watching. I calculated it in my head as 7/.15 which is equal to 700/15 which is equal to 1400/30 or 140/3. And I got 46 and 2/3.
Not understanding the given answer. If you intend to limit the answer to one decimal place then the answer is 46.7
Two decimal places is 46.67
Three decimal places is 46.667
46.6 is incorrect.
Neither gives the exact answer, just approximations.
H’mmmm Na! What age group are you identifying with? 4 minutes in, still no progress on the problem! And then you start talking about calculators!? WTF? What The Facts! You got a calculator on your shoulders ....Brain....that’s what we should elect to use when solving on the run % challenges! Such as in a store or in conversation....Now show them (Us) how to use our god given calculator....You reminded me about being in school decades ago, and nothing seems to have improved! Regards to your effort, but not good enough for my five year old! Who is in the 21st Century “Mental arithmetic” denial!
I earned a handful of stars... but didn't do the problem as you. I simply made 15% into a fraction 15/100 and made an equivalent fraction... 7/x so 7/x = 15/100 cross multiply and divide .... so 7*100 = 15x 700 = 15x ... 700/15 = 15x/15 .... 46.666... = x I used equivalent fractions to solve the problem. It is so easy. You don't need an example and then apply the example. You just need to know that 15% is 15 of 100 and you want to know the denominator that goes with 7 to make a pair of equivalent fractions to 15/100.
7 is 15% of what number
I will try before watching the video..
7 is =
15% of what number = 15/100(x)
7 = 15/100 x
7/1=15/100x
100*7=15x
700=15x
x=700/15
x=46.67
Actually I solved this in my head without all the hoops. I asked what percent of 100 is 15... thats pretty easy 6 15's is 90 leaving 10 which is obviously 2/3rds of 15 thus 6.66 is the percentage that 15 is to 100... then simply multiply 7 times 6.6 six times seven is 42... 2/3rds of 7 is 4.6 there's your answer 46.6 no pencil required.
Greetings. The answer can be determined by assuming that the number is X. Now 15% of X = 7, and
3X=7×20. That is 3X=140 and
X=140/3 =46.6 recurring, rounded to
46.7. The number is 46.7.
7/3 =2.33... (5%)
2.33 x 2 = 4.66 (10%)
4.66 x 10 = 46.66... (100%)
If 7 is 15% of a number then 7/15 is 1% and 700/15 is 100% = 46.67. What's the mystery?
It took about a second to work that out so why is the video almost 15 minutes long, especially as I only needed 0.114% of the length of the video to come to the same conclusion?
This video makes me glad I left school at 15
I just watched this video. I understand that you want to teach a particular lesson here, but I have a question. Isn't this particular problem solveable in an easier and still correct way? I mean if you know that 7 is 15% of x, then you also know that 1% of x is 1/15 of 7. So if you divide 7 by 15 and multiply the answer by 100, you get the value of x. I realize there are multiple ways to solving problems, it just seemed to make sense to me, to do it the shortest way. I love your channel, the problems help stimulate my aging mind. :)
Way too much jaw time.
Teach students to speak math.
“7 is 15% of what”
“is” means equals
“%” means hundredths
“of” means times
Translation:
“7 = 15/100 • n”
or
“7 = .15 • n”
Complex.... Just take 10% instead of 15%. That would be 70. Ratio 10% to 15% is 2 to 3. Just divide 70 by 3, and multiply by 2. That is 46.6666
How would you put 46.6...in the form of a fraction like trying to find [(13/17)= the decimal 00.7647058823529411...back to (13/17)].
This video lasts for 14.6 minutes.
468884 people have watched it so far.
(466884 x 14.6 ) /(60 x 24 x 365 ) > 13
You have wasted more than 13 years worth of people's time on this utterly trivial problem
decimals are inadequate for expressing the solution to this problem: if 7 is 15%, then one third of this is 5%. 7 divided by three is two and a third. Double this and you have 10% of the total - 4 and two thirds. Multiply this by 10, you have 100% of the amount. 4 x 10 = 40 and two thirds x 10 = 20 thirds. Twenty thirds is 6 and two thirds, so 46 and two thirds is the most accurate expression of the full amount :)
I did in my head:
7 would be 10% of 70.
15% would be 2/3 value of 70.
1/3 = 23.33 × 2 = 46.66
Why not just jump to the basic equation that comes down to this:
0.15X = 7
X = 7/0.15
therefore X = 46.7
You also go on and on with stories that have nothing to do with learning math, and examples that just leads one astray.
I am a probuct of the California special education I had a really hard time with all the subjects in school and somehow graduated in 1987 ... usually having a really hard time with handling a job for very long just because I am always feeling like I am at the bottom of the employment totompole never able to move up right now working at Goodwill 4 some 4 years of doing the same duties over and over ... keep feeling if I understand math a little better maybe my life would be better..not dumb or a crackhead no criminal history it's just at 54 most of the time I feel Iam still that kid floating though high school back in 1987 ..from Ventura high school now live in Klamath falls Oregon,. keeps feeling if I understand math and computers couldn't understand what x and y was on a graph calculate .try hard not to be sick or late for work just at Goodwill the will never move me up watching a lot of people come and go Goodwill is one of those jobs is just really hard to get a head . I will talk alot about pie R square...and I don't know what else I can do at 50 something..or if I have to start over at a new job I have to start at the bottom a long with all the other high school kids .. thanks for your time you and listen good night from Klamath falls Oregon
you got to 5 minutes and then I gave up when you went wandering off again. what you should do, in my opinion, is put the answer up front and then piece by piece explain why it is the answer. Something after the style of: if 7 is 15% then 1% is 7/15 and 100% would be 100 x that. Write that out in numbers or something. Go on from there. This is simply obfuscation by preamble and anecdote.
Four minutes in and still no answer. I go to an online percentage calculator. 46.6666
I pity those adults who can't estimate this in their head in a few seconds. My brain came up with something around 45. Calculator was 46.666. 7 divided by .15. Cripes.
Fifteen minutes? It's literally 7 = (15/100) x, and so x = 700/15 = 140/3 = 46 2/3.
"Percent" just means "divided by 100".
7 is 15% of what number?
I done it as times both numbers by 10..
70 = 150%
70 /3 = 23.3333r (50%)
x2 = 46.666666667
Hahahahahaha 🤣
I’ve watched a handful of your videos because you’re doing exactly the questions I’m currently interested in. But every video I’ve watched is about 90 or more percent chat and a tiny bit of time addressing the math problem which represents my only motive for watching. I’m going to try to avoid any more of your videos.
105? 10% of 70 = 7 so 15% of 105 = 7
Question is if you can calculate this in less than 14 minutes. Elsewize the pub-quiz had finished either you.
7/15*100=46.6666 that's all
15% = 15/100 = 3/20 then 3/20 x N = 7 or N = 7 x 20/3 = 140/3 = 120/3 + 18/3 + 2/3 = 46 2/3
This is the exact answer and no calculator needed !
In my head I did 7 is 15% so 14 is 30%, so 14/3 is 10%. 14/3 is 4 and 2/3 or 4.66 which, x 10, is 46.6 No calculator, just old school common sense really.
How about dividing 7 by .15. Result is 46.666667. Close enough for government work? Don't make it harder than it needs to be.
Convert % percent to decimal equivalent. 15% = 0.15. Then divide 7 by 0.15 (7/.15), which is 46.667.
14.667 times 0 .15 (15 %) So 46.667 times 15% (0.15) = 7. Instead of 15%, use 50%. If 7 is 50% (1/2) of some number, then the number is 14.
You totally lost me on your 2nd line. 14.667 time 0.15 = 2.20005. What does that have to do with the problem? And what does this thing with 50% have to do with the problem?
Boy - how to make your self seem clever by overcomplicating a simple equation.... x = 7 x 100 / 15. 10 seconds to work that one out.
7/.15
Then double checked 46.667x 0.15
Maybe double checking doesn't count? Is this question a joke?
what a load of malarky.
1% of the unknown number is 7 divided by 15
the number is now the answer to the above multiplied by 100. 46.6
no wonder people are so poor at maths
70=150%
50% =23.33
100%=46,66
I thank you very much for the time you spent putting together with William comments below. I wish you went straight to the issue; to solve the problem w/o so much jargon. Try to make it straight up, without so many other examples of other percentages and what have you. You seem to drift off the point.
Long minutes of blablabla, for nothing. I'm not a mathematician and i resolved this problem in a few seconds. Sorry for my incorrect english, i'm french.
You don't really need "step by step". Just divide 700 by 15.
OK...2 minutes into the video and this guy is just yammering on and on and not showing how to work the problem but selling hisself! Yo dude...give us a timeline so we don't have to listen to all your bull!