Math just got important! Which sector of pizza is a better deal? Reddit r/sciencememes

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  • Опубліковано 20 гру 2024

КОМЕНТАРІ • 2,1 тис.

  • @bprpmathbasics
    @bprpmathbasics  5 місяців тому +122

    1 divided by 0 (a 3rd grade teacher & principal both got it wrong), Reddit r/NoStupidQuestions
    ua-cam.com/video/WI_qPBQhJSM/v-deo.html

  • @qwertek8413
    @qwertek8413 5 місяців тому +6566

    If the radius of pizza is z, and the thickness is a, the volume of the entire pizza is just pizza.

  • @richardhole8429
    @richardhole8429 5 місяців тому +1771

    I am so sorry. I ate both pieces while attempting to solve.

    • @sureshmukhi2316
      @sureshmukhi2316 5 місяців тому +11

      😂

    • @perrinromney4555
      @perrinromney4555 5 місяців тому +44

      Which one took longer to eat? If you can determine that, we have ourselves an empirical solution.

    • @keescanalfp5143
      @keescanalfp5143 4 місяці тому +14

      ​@@perrinromney4555,
      it'll always be the second i eat , just because it is the second , and because the difference between the volumes is rather small, as for my mouth .

    • @webpombo7765
      @webpombo7765 4 місяці тому +3

      ​@@keescanalfp5143 I disagree, I don't think the second one would be slower just because it's the second one for me

    • @facesmelt9903
      @facesmelt9903 3 місяці тому +8

      Yeah once I heard pi I started eating the whole pie

  • @Sockerrus
    @Sockerrus 5 місяців тому +2686

    This is a perfect example for kids in school asking when they will ever use math outside of school.

    • @deivisnx
      @deivisnx 5 місяців тому +48

      Yeah, except i can use a calculator sooo...

    • @sergio73master1
      @sergio73master1 5 місяців тому +67

      And except kids nowdays don't give a fck about the price or economy in general. The next Tik-tok video resets their worries...

    • @KingAfrica4
      @KingAfrica4 5 місяців тому +279

      ​@@deivisnxcalculator not useful if you don't know the formula...

    • @rebane2001
      @rebane2001 5 місяців тому +26

      ​@@KingAfrica4you don't even need to know the formula by heart, just that it exists and that it's applicable here

    • @josevictorribeirolisboa7576
      @josevictorribeirolisboa7576 5 місяців тому +35

      Pretty sure people wouldn't use this for pizza. Nobody is going to use math for that.

  • @twitchcontrols1441
    @twitchcontrols1441 4 дні тому +56

    This unit took a week to teach in my precalc class. This dude made me care about the subject and taught the material in 4 minutes.

    • @ThisDique
      @ThisDique 20 годин тому +1

      This is elementary geometry dude. I'm disappointed to hear that lol.

    • @twitchcontrols1441
      @twitchcontrols1441 19 годин тому +1

      @ introducing sin/cosin/tangent, radians, and arc lengths didn’t happen till high school dude.

    • @Riley_Mundt
      @Riley_Mundt 4 години тому

      ​@@twitchcontrols1441These aren't right triangles, so sin/cos/tan is irrelevant. These aren't even triangles, they are just segments of a circle. Area of a circle and basic division are taught at the third grade, any on-level eight year old will be able to solve this.

  • @GoldenLeafsMovies
    @GoldenLeafsMovies 5 місяців тому +711

    Bro has the quickswap skill unlocked for switching markers.

    • @PEECTPA
      @PEECTPA 3 місяці тому +8

      That exactly what i was thinking the whole video! Sad, but true

  • @daroxes6399
    @daroxes6399 5 місяців тому +2520

    Everybody's out there doing actual maths and I'm here just counting the number of pieces of pepperoni and being objectively correct.

    • @brownfamily1892
      @brownfamily1892 5 місяців тому +196

      This is the only correct method

    • @eminkilicaslan8945
      @eminkilicaslan8945 5 місяців тому +160

      7" pizza has more pepperoni tho, but 6" pizza is more pizza per dollar.

    • @dark6.6E-34
      @dark6.6E-34 5 місяців тому +82

      Dont forget the pictures on display can be misleading.

    • @0x1EGEN
      @0x1EGEN 5 місяців тому +28

      The question is about which has better price to size ratio, not which slice is bigger. 7 inch pizza is larger but also costs more.

    • @baranjan6969
      @baranjan6969 5 місяців тому +12

      I just craft a glass bottle with those shapes and measure how many liters it takes to fill.

  • @marcush4741
    @marcush4741 5 місяців тому +1057

    On paper, the first one is a better deal. But we cant forget that a larger angle means more crust. We should look at the ratio of crust to non crust as well.

    • @russellharrell2747
      @russellharrell2747 5 місяців тому +215

      Some people like more crust, especially if it’s stuffed.

    • @marcush4741
      @marcush4741 5 місяців тому +178

      @@russellharrell2747 absolutely fair. Still, crust to pizza ratio is definitely worth looking into.

    • @GG-mb9rr
      @GG-mb9rr 5 місяців тому +9

      Or dipping sauce

    • @kylen6430
      @kylen6430 5 місяців тому +42

      While I agree with your point that crust is an important consideration, I just want to point out that a larger angle doesn’t strictly mean more crust. Both angle and radius are a factor, but in this case, yes the 6in piece has more crust

    • @Zack_Zander
      @Zack_Zander 5 місяців тому +11

      ⁠@@russellharrell2747
      Yep, I don't like the crust *_unless_* it is stuffed.
      Like, I would eat it in a group situation, but if I have the choice, I’ll skip it.

  • @wobaguk
    @wobaguk 5 місяців тому +1283

    Since Pi is a common factor in the two areas, you can disregard that in the calculation and keep the maths easier.

    • @theodoremurdock9984
      @theodoremurdock9984 5 місяців тому +66

      1/360 is also a common factor that cancels out when you set up the ratio (also the units cancel out as long as they match, e.g. the ratio here is in square inches of pizza per square inch of pizza).

    • @feuerschlange6374
      @feuerschlange6374 5 місяців тому +77

      ​@@theodoremurdock9984 no, angle/360 does not cancel out.
      One being 45/360 = 1/8
      And the other 60/360 = 1/6
      That leaves you with 49*(1/8)*pi
      And 36*(1/6)*pi
      Since pi is in both only another factor you can ingore pi

    • @CornyFlakez
      @CornyFlakez 5 місяців тому +116

      ​@@feuerschlange6374 nobody said anything about cancelling angle/360. They said that 1/360 is a common factor, which can be cancelled in both calculations.
      i.e. 60pi×6² and 45pi×7²
      However, the way I did it mentally was simplifying the fraction and expanding the square.
      ⅙pi×36 vs ⅛pi×49
      pi can get cancelled
      6 vs 49/8 = 6⅛
      so the right one is slightly larger but proportionally much more expensive. So i estimated the left one is more worth it.

    • @peterpan408
      @peterpan408 5 місяців тому +12

      This would answer which is cheaper on a per area basis, but not tell you how much on a per area basis. But it wasn't asked so do it.

    • @GamingWithUncleJon
      @GamingWithUncleJon 5 місяців тому +26

      ​@@peterpan408so don't waste time on irrelevant calculations.

  • @youuuuuuuuuuutube
    @youuuuuuuuuuutube Місяць тому +170

    As an engineer, you don't need to calculate the exact area, just do: 60 * 36 / 1.5, and 45 * 49 / 1.7 => bigger number wins (meaning left with $1.50). Basically skip the PI and 360.

    • @aerophage
      @aerophage Місяць тому +24

      I came here to say this, but I'm glad to see it was already said. All we care about is the ratio

    • @HotCrossJuns
      @HotCrossJuns Місяць тому +19

      Least relevant "As an engineer..." of all time

    • @mykeyboardismelting6856
      @mykeyboardismelting6856 Місяць тому +5

      I mean yeah the ratio stays the same when you remove 1/360 and pi from both the numerator and denominator, but that’s only helpful for simplifying the final calculation when you know you have two sectors.

    • @MiccaPhone
      @MiccaPhone Місяць тому +8

      Hello Howard Wolowitz, also non-engineers are allowed to skip PI and 360, the result won't change for non-engineers.

    • @MiccaPhone
      @MiccaPhone Місяць тому +4

      As a non-engineer you can do the exact same thing!

  • @jamiew7805
    @jamiew7805 5 місяців тому +88

    This is the type of question the teacher goes over in class that everyone loves and asks to be on the test.. then asks on the test as the final question “what width does the crust have to be for both pizzas (to the nearest quarter of an inch) for the deals to be equal for the cheese part?” .. simply to gauge if you truly understand what’s at stake in the original question.

    • @rockoutconsiderably
      @rockoutconsiderably 5 місяців тому +1

      I would love a video on how to figure this out please

    • @jacktumba375
      @jacktumba375 3 дні тому +1

      ​@@rockoutconsiderablyheres a hint. Take the sector area formula, but set r to (radius - crust width). Plug in values, solve.

  • @realDonaldMcElvy
    @realDonaldMcElvy 5 місяців тому +885

    I dunno man, you gotta consider the Crust Factor. The 1st Slice has a larger portion of the perimeter, thus more of a Crust/Cheese Ratio. Meanwhile, the 2nd Slice has less of a Crust Factor, and thus is appreciated at a higher value.

    • @Verxinn
      @Verxinn 5 місяців тому +176

      Don't forget the ergonomic aspect of pizza eating, its much easier and enjoyable to eat a thinner and longer slice

    • @ramennoodle2085
      @ramennoodle2085 5 місяців тому +86

      Crust is the best part.

    • @highviewbarbell
      @highviewbarbell 5 місяців тому +41

      ​@@Verxinnones worth is determined by their girth

    • @vincentlamontagne7639
      @vincentlamontagne7639 5 місяців тому +19

      Assuming a contant 1 inch wide crust of both pizzas, pizza #2 has a better cost to toppings area ratio!

    • @patrickd9551
      @patrickd9551 5 місяців тому +9

      @@vincentlamontagne7639 Euhmmm, no. I actually started out writing a comment exactly to this degree. But in fact the smaller pizza still has more area thanks to the larger angle. I was actually considering a partial value to the crust and was midway through the math when I decided to first check the basic math portion of it. Sooooo, I deleted the comment ;)

  • @Zufalligeule
    @Zufalligeule 5 місяців тому +107

    I've used a bit different method to solve this:
    1. Divide the area for the bigger piece by the area of the smaller piece (pi's and 360's cancel out). I've got 45/60*(7^2)/(6^2) = 1.02 or 2% growth in area for the bigger piece.
    2. Divide the prices: 1.70/1.50 = 1.13 or 13% growth in price for the bigger piece.
    3. Since the growth in price is bigger than growth in area, smaller piece will be a better deal.

    • @richard7199
      @richard7199 5 місяців тому +2

      I just did 25 cents per inch and came up with 5 cent save for the 7 inch slice lol

    • @mawillix2018
      @mawillix2018 5 місяців тому +5

      @richard7199
      You forgot that the 7 inch pizza is thinner.
      With your logic a 10 by 1 rectangle of pizza is better than a 9 by 9 square of pizza.

    • @richard7199
      @richard7199 5 місяців тому +1

      @@mawillix2018 I never said we’d get more food from it, merely that we get more inches of pizza.

    • @SunDry_Marchy
      @SunDry_Marchy 5 місяців тому

      And you were wrong on both occasions. You aren't measuring length of pizza to determine what's better cost-wise, you use the volume (well, not exactly, we won't be able to properly calculate V, so S is fairly sufficient) ​@@richard7199

    • @mawillix2018
      @mawillix2018 5 місяців тому +2

      @@richard7199 That depends on how you measure the pizza.

  • @thinkeightsix
    @thinkeightsix 5 місяців тому +111

    Next time I see someone pull out a whiteboard while waiting in line to buy a slice, now I'll know why.

  • @charlesxavier1904
    @charlesxavier1904 5 місяців тому +213

    It's better if you just grab a slice and carry on with how close both of these are. If I'm getting paid minimum wage of 7.25 an hour and I'm doing roughly 4:32 seconds worth of work. That comes out to roughly 54 cents of time to calculate this problem. So it costs more money to calculate the unit price of these two similar pizzas than the money you lose by randomly picking the slice of those two closely sized slices.

    • @HarmonisedMelody
      @HarmonisedMelody 3 місяці тому +57

      True. But if you travel this path often and you're doing the math on your walk home, time lost regardless, you come out significantly ahead in your savings for easy calories! I'd also want to know the bread thickness and topping density though to make a real calculation 😂

    • @stella.excite
      @stella.excite 3 місяці тому +19

      If we hold a strictly linear time-to-money conversion based on minimum wage, then yes. I agree both technically and in spirit, so I liked the comment.
      That being said, the situation may be that money, not time, is the limiting factor. If for whatever reason, you cannot freely take on more hours of work and any reliable investment ties up your funds, you may find yourself with free time (at least enough to watch this video) that cannot easily be converted to cash, and low enough cash you feel obliged to make every penny count.
      That being said, for almost any practical purpose, just pick a slice and roll with it. They're close enough in size and cost where a problem like "3 small vs 2 large" is unlikely to be applicable, so the only reason to bother is because you like doing the math (which tbf, watching this video indicates you do.)

    • @Sasquatch-ff1pj
      @Sasquatch-ff1pj 3 місяці тому +15

      This type of problem solving matters in bulk. Say you had to order thousands of slices of pizza a week. Now the savings actually accumulate into viable money.

    • @Chris_Fer
      @Chris_Fer 3 місяці тому +3

      ​@@Sasquatch-ff1pj
      Plus you get the pleasure of giving the 🖕To the ones trying to rip you off.
      I hate being taken advantage of 🤬

    • @maudley
      @maudley 2 місяці тому +5

      But you only have to solve it once, and one is about 12.5% more expensive per inch than the other. How many times do you have to buy it before the savings offset the time lost to calculate?

  • @LithmusEarth
    @LithmusEarth 13 годин тому +5

    The next video listed at 4:31 is "the trickiest 1% Question: in a room of 100, 99% are left-handed. How many must leave to get 98%" Well look at it another way we have 1 = 1%100 right handed and we want 1 = 2%X; So 1 = 0.02X; 50 = X; So 50 People must remain, so 50 Left Handed People have to leave? to make 1vs49 to be 2%.

  • @danny1103
    @danny1103 5 місяців тому +320

    Real life example: Costco Pizza always have the best deal, very large, fairly affordable, and no need the hassle on figuring out which coupon to apply that provide the most mathematical and financial advantage.

    • @bokkenka
      @bokkenka 5 місяців тому +19

      Sure... Much like Ikea, they hope you leave with a good feeling about the food (Wow! That was a great deal!) so that it translates into a good feeling overall about shopping there. First impressions are important, but so are last impressions.

    • @danny1103
      @danny1103 5 місяців тому +14

      ​@@bokkenka I am still using my 15 year 70 inch desk from IKEA that was like $109 back then. The desk is still smooth and strong after moving like 5-8 times from house to house.

    • @johnpaullogan1365
      @johnpaullogan1365 5 місяців тому +12

      but you have to calculate the cost of an hour drive to get to a costco and the cost of the costco membership. math gets complicated.

    • @NO1xANIMExFAN
      @NO1xANIMExFAN 5 місяців тому

      ​@@johnpaullogan1365the deals and frequency and amount of stuff I buy more than justifies the car drive and membership. It's a no brainer...

    • @sabin97
      @sabin97 5 місяців тому

      @@johnpaullogan1365
      those "members only" shops CAN be a good idea. if you go there often and buy a lot, because those small savings add up.
      but if you dont buy a lot, it's mostly not worth it.

  • @davidellis1929
    @davidellis1929 5 місяців тому +74

    The volume of a cylindrical pizza with radius Z and thickness A spells PIZZA.

  • @Nomimasu
    @Nomimasu 5 місяців тому +227

    With just a couple of tricks you actually don't have to calculate exact values. First pizza has 36 square units for 9 bucks, so it's 4 units for $1. Second pizza has 49 units for 1.7*8 = $13.6, but for $13 we can buy 52 units of the first pizza. So, first is cheaper.

    • @tranmanhuc6235
      @tranmanhuc6235 5 місяців тому +2

      i did the same thing

    • @User_305aq2
      @User_305aq2 5 місяців тому +32

      My brain said, "bigger angle, not big difference in size, lower cost. Go with bigger for less cost."
      No need for math.

    • @OrangeC7
      @OrangeC7 5 місяців тому +1

      I did something similar but I did some division so I had to use a calculator for the last bit. Using just multiplication is a lot nicer

    • @gaia9020
      @gaia9020 5 місяців тому +6

      The number of pieces does not take in account the diameter or radius of the individual pizza. The first has a diameter of 12, the second of 14, so the second might still be the better deal due to it being larger, thus to just count the pieces is not sufficent :)

    • @Apollorion
      @Apollorion 5 місяців тому +5

      @@gaia9020 I think you misunderstood Nomimasu's OP. Nomimasu spoke of _square unit_ which I think was a unit for surface area, i.e. square inch over pi. The numbers of calculation shown were acquired by filling up the discs & realizing that the surface area of a disc is proportional to the square of their radius a.w.a. that the constants that reappear in the expressions for both discs cancel each other out when comparing the two discs.

  • @TealRubyy
    @TealRubyy 5 місяців тому +4

    You can vastly simplify since in calculating the area, pi is a common factor. Just square the length and divide by the number of slices you could slice (60 is 6 slices, 45 is 8 slices). You don't even have to consider price at that point because it will be apparent that the 7in pizza has marginally greater area but costs a lot more.

  • @willkpc
    @willkpc 21 годину тому +2

    But first one has more crust! This needs to be reconsidered and recalculated.

  • @neilgerace355
    @neilgerace355 5 місяців тому +543

    Cut through the whole mess by never getting less than a whole pizza!

    • @jabbawookeez01
      @jabbawookeez01 5 місяців тому +22

      thats y you get like the $6 little ceaser pizza or something and you get to enjoy it yourself. 💀

    • @taito404
      @taito404 5 місяців тому +3

      Ooh. I like that thinking. Very creative

    • @ailst
      @ailst 5 місяців тому +36

      In this case you still have to be able to calculate whether a 24 cm diameter for 4 € is a better deal then the 28 cm diameter for 6 €!
      And multiplying segment angle/360 is just one relatively easy additional step.

    • @neilgerace355
      @neilgerace355 5 місяців тому +2

      @@ailst That's all true, but you still end up with more pizza :)

    • @jamesharmon4994
      @jamesharmon4994 5 місяців тому +10

      ​@neilgerace355 The question isn't which pizza is bigger, the question is which is the better value. Three is bigger than one, of course. But which should you choose if given the option $1 each versus three for $5. The one, of course. 😅

  • @zeroone8800
    @zeroone8800 5 місяців тому +153

    Since you are only comparing the price/area of the two slices, pi cancels out and need not be calculated.

    • @MikehMike01
      @MikehMike01 5 місяців тому +15

      The 360 as well
      But then you will only be determining the better value and not the specific values

    • @msolec2000
      @msolec2000 5 місяців тому +4

      Also the 360º in the denominator cancels out

    • @zeroone8800
      @zeroone8800 5 місяців тому +15

      @@msolec2000 I prefer to instead reduce the angles to 1/6 and 1/8. The areas then become 6(pi) and 49/8*(pi).

    • @ajejebrazov2
      @ajejebrazov2 5 місяців тому +5

      ​@@zeroone8800I did the same,so no need to approximate, which always introduce error

    • @57thorns
      @57thorns 5 місяців тому +5

      @@zeroone8800 Yes, and the of course pi goes away as well, which is a shame as I like pie as well as pizza.

  • @3dbyeb971
    @3dbyeb971 5 місяців тому +101

    Now calculate how much more crust you are buying on the 6" slice.

    • @jamesharmon4994
      @jamesharmon4994 5 місяців тому +19

      Eat the crust!! 😅

    • @Snaproductions
      @Snaproductions 5 місяців тому +12

      the frust is good

    • @MrSparkefrostie
      @MrSparkefrostie 5 місяців тому +5

      That's the best part, that just improves the value of the 6' slice

    • @janb.3600
      @janb.3600 5 місяців тому +1

      The 60° slice has 8/7 times the crust of the 45° slice, which makes it better.

    • @phiefer3
      @phiefer3 5 місяців тому +4

      Assuming the crust is about 1 inch thick, the 6 inch slice has a better price per crust ratio AND a better topping per price ratio than the 7 inch slice.

  • @Hyloshit
    @Hyloshit 5 місяців тому +2

    This is why I always bring a kitchen scale so i dont have to do math for pizza.

  • @jeffmarner3106
    @jeffmarner3106 Місяць тому +3

    Crust must be calculated. If we estimate .5” of crust the 6” pizza is about $.095/in while the 7” slice is about $.103/in. So the 6” is still barely a better deal but no pizzeria is having that little crust. In almost every real world situation, the 7” will be the better deal. And sometimes the toppings aren’t perfectly centered so be sure to select the correct piece.

  • @Wise_That
    @Wise_That 5 місяців тому +131

    49/36*6/8 = means second slice is 2% bigger but ~15% more expensive.

    • @oliverschell7014
      @oliverschell7014 5 місяців тому +7

      Yes, but 13 % more expensive.

    • @GamerNineSix
      @GamerNineSix 5 місяців тому +4

      But also less crust

    • @lupolinar
      @lupolinar 5 місяців тому +3

      Also more salami slices

    • @Zhcwu
      @Zhcwu 5 місяців тому +2

      Bread costs nothing but good pepperoni and cheese costs a lot.

  • @0x0404
    @0x0404 5 місяців тому +90

    Theoretically the thinner longer slice will be better since it will have less of that outer edge crust depending how much it takes up

    • @martygreenspan-xy2jo
      @martygreenspan-xy2jo 5 місяців тому +9

      Exactly! You have to take into account what portion of each is crust, cause everyone knows that cheesybites > crustybites.

    • @theNaluK
      @theNaluK 5 місяців тому

      This is exactly what I was thinking!

    • @GG-mb9rr
      @GG-mb9rr 5 місяців тому +6

      Not if you have dipping sauce for the crust

    • @Zakon213
      @Zakon213 5 місяців тому

      Similarly, when I compute the value of pizza, I subtract 1 inch from the radius due to the crust

    • @macromite3758
      @macromite3758 5 місяців тому +7

      outer edge crust is the best part. if you don't like it then you are a baby.

  • @fifiwoof1969
    @fifiwoof1969 5 місяців тому +8

    Gotta love unit pricing - VERY useful at the grocery store! In Australia the grocery has to show you the unit price on the shelf - EASY PEASY!

    • @johnpaullogan1365
      @johnpaullogan1365 5 місяців тому +1

      my grocery store does unit pricing but 3 brands of the same product one will give price per serving, one price per ounce and the 3rd will give price per gram

    • @sabin97
      @sabin97 5 місяців тому +1

      i do this all the time.
      particularly when buying rice.
      for some reason the larger packets of rice arent always cheaper per unit.
      sometimes it's cheaper per unit to buy 2 small packets than a large one....so i always do the maths.....numbers dont lie. "common sense" does.

    • @fifiwoof1969
      @fifiwoof1969 5 місяців тому +1

      @johnpaullogan1365 clearly they hate customers by mixing up units.
      Luckily in Australia the units match so the comparison is VERY easy to compare!

  • @Fridgeson_
    @Fridgeson_ 3 дні тому +2

    Have 4 bucks,
    buy both slices,
    give the 80 cents tip to the cashier.
    Economy

  • @andrewshiff2004
    @andrewshiff2004 5 місяців тому +2

    I simply figured how much each pizza would cost once you added each slice to equal 360*.
    A) 1.50 x 6 =$9
    B) 1.70 X 8 = $13.60
    Knowing that two more slices of A would still be less costly than B. However, if B was better quality and taste and there were only two people sharing the pizza B would be the better choice. Simply based on shared experience.

  • @davidellis1929
    @davidellis1929 5 місяців тому +30

    You don't need to calculate the areas, just the ratio of 36/6 to 49/8. The latter shows the narrow slice is just barely larger, by a lesser factor than the price differential.

    • @abacaabaca8131
      @abacaabaca8131 5 місяців тому +5

      But you still need to consider the price factor.
      Like so:
      1.50/(36/6) vs 1.70/(49/8)

    • @johnpaullogan1365
      @johnpaullogan1365 5 місяців тому +4

      @@abacaabaca8131 or just check if 1.5*(49/8)/(36/6) is less than 1.7. simplifying gives us (3/2)*49/48) on the left side which is 147/96 which is 1.53125. so unless the second slice is less than that it is a worse deal

    • @meurdesoifphilippe5405
      @meurdesoifphilippe5405 5 місяців тому +1

      Yes, or compare 36*4, and 49*3, so 144 vs 147. Almost same area, while the difference in prices is much greater.

    • @snestah
      @snestah 5 місяців тому +2

      Yeah, this is simpler to compare with fractions and highlights why you need to be comfortable with using fractions and decimals. No need to calculate pi, save time to eat the pie.

    • @BlacksheepY-l8q
      @BlacksheepY-l8q 7 днів тому

      Why not just ratio of 6/6 and 7/8. What’s the purpose of square here if all you care about is compare magnitude

  • @ironfoot1938
    @ironfoot1938 5 місяців тому +40

    I'm disapointed that you didn't use a short cut to calculate it:
    You don't have to calculate the /360 and the * π as they are both equal factors. So having to compare them you can just work with rational numbers:
    6^2* 60 / 1.50 vs 7^2 * 45 / 1.70

    • @davesimms8825
      @davesimms8825 5 місяців тому

      That’s how I did it.

    • @TheFantasticWarrior
      @TheFantasticWarrior 5 місяців тому

      That makes the number bigger though, 1/6 and 1/8 is just easier

    • @chrisschack9716
      @chrisschack9716 5 місяців тому +4

      The /360 is easy to deal with here, it just factors out so it's 1/6 or 1/8 ... and that 1/6 further cancels against the 6^2

    • @mynameisnotjeff4184
      @mynameisnotjeff4184 5 місяців тому

      Im disappointed a double integral wasn't used to calculate the area

  • @robertonoz616
    @robertonoz616 5 місяців тому +24

    Love this problem. Gave it to my students once and as a bonus had them calculate how long the pizza would have to be for them to get the same deal if the pizza was only 1° wide lol

    • @R2Bl3nd
      @R2Bl3nd 5 місяців тому +5

      I would love to eat a pizza like that. It would be like having a conveyor belt made of crust, which is carrying sauce, cheese and toppings into my mouth.

    • @johnpaullogan1365
      @johnpaullogan1365 5 місяців тому

      so a 1/2" radius pizza with a 45 degree arc? or a different radius and theta such that the length of the arc measures 1 inch but the area of that section of the pizza is such that it is 17/15 the area of the first?

    • @HeShoeTooBig
      @HeShoeTooBig 5 місяців тому

      If I were a student, i would have just said "it'd be more efficient to just weigh slices."
      Seriously, by the time you solve this, the pizza done got cold.

  • @Momie_et_Masque
    @Momie_et_Masque 3 місяці тому +2

    but there are less ingredients on the border of the pizza than on the inside so the pizza with longer radius has a better inside/border ratio

  • @thechatter7102
    @thechatter7102 4 місяці тому +2

    holding on to pi until the final step is always more satisfying

  • @lool8421
    @lool8421 5 місяців тому +7

    1st slice is 1/6 of a circle
    2nd slice is 1/8 of a circle
    surface area is pi*r^2
    1st slice: 36pi/6 in^2
    2nd slice: 49pi/8 in^2
    now just make the bottoms the same to compare the sizes
    288pi/48 in^2
    294pi/48 in^2
    seems like the 2nd pizza is better? well, it's bigger by about 2% but it's more expensive by 12-13%, so the first slice wins
    unless you really hate the edge, then the 2nd pizza is better

  • @rpfour4
    @rpfour4 5 місяців тому +18

    I dunno. The 2nd pizza has more pepperoni.

    • @hemandy94
      @hemandy94 5 місяців тому

      That's why it is 20 cents higher

    • @werdwerdus
      @werdwerdus 5 місяців тому +2

      of course it has more pepperoni, the total area is larger. the question is meant to measure value not absolute amounts

    • @LS-sx5qo
      @LS-sx5qo 2 дні тому

      ​@@werdwerdusNo, the question is about which is the better deal.

  • @sarkedev
    @sarkedev 3 місяці тому +3

    Not enough information to solve. What if they're stuffed crust?

  • @Kalvirl
    @Kalvirl 3 дні тому +1

    The easiest way to teach a New Yorker math

  • @mengkhang1037
    @mengkhang1037 5 місяців тому +2

    My math is how many pieces of pepperoni am I getting over the other one. Which ever one has more I'm buying.

  • @R3LI2UI
    @R3LI2UI 5 місяців тому +10

    Actually, it did, but not in the way you might think. 6" slice has 7.5 pieces of pepperoni @ cost of $1.50. 7" slice has 8.75 pieces of pepperoni @ $1.70: 6" = $1.5/7.5 = $0.20 per slice of pepperoni, 7" = $1.7/8.75 =$0.19 per slice of pepperoni...7" slice is more cost effective at a penny less per slice of pepperoni. Cost of making pizza [manhours] is same regardless, cheese & sauce are fairly comparable across the two; pepperoni is most expensive ingredient on the pie. 8) Area of slice may be larger, but you're getting a more expensive meat topping.

    • @ABaumstumpf
      @ABaumstumpf 5 місяців тому +1

      i would say it is only 8.5 slices on the 7" - so value for that, but everything else is more.

    • @R3LI2UI
      @R3LI2UI 5 місяців тому +1

      @@ABaumstumpf Point [tongue-in-cheek] was meant to show there's more to the calculus than sheer geometry; otherwise agreed. 8)

    • @werdwerdus
      @werdwerdus 5 місяців тому +1

      that's fine if all you care about is maximizing total pepperoni. but that is obvious to see since the 2nd one has a larger total area. some of us prefer more crust so the first one wins in both price per unit area as well as more crust

  • @bluegizmo1983
    @bluegizmo1983 5 місяців тому +8

    0:48 NO, it's called a Slice of pizza, not a Sector or pizza! 😂

    • @cat7930
      @cat7930 Місяць тому +1

      Wrong channel

    • @Axcyantol
      @Axcyantol Місяць тому

      @@cat7930what

  • @jondycz
    @jondycz 22 дні тому +1

    Just count the number of pepperonis

  • @deadSKX
    @deadSKX 2 дні тому +1

    i will still take the 7 inch one because the picture at the start of the video had more pepperoni on it🍕

  • @mikefochtman7164
    @mikefochtman7164 5 місяців тому +25

    Now let's add the thickness. If the first pizza slice is 'thin and crispy' with thickness of 3/8 inch and the second is 'deep dish' with thickness of 1 inch.... lol

    • @dannyyeung8237
      @dannyyeung8237 5 місяців тому +5

      Yeah thickness is important as well

    • @shaurryabaheti
      @shaurryabaheti 5 місяців тому +2

      why not include the toppings count and crust width at the edges

    • @werdwerdus
      @werdwerdus 5 місяців тому

      this and crispy will ALWAYS lose to total amount of pizza per price haha. it's like a cracker with sauce and cheese. but it's never any cheaper than hand tossed crust

    • @h4z4rd1000
      @h4z4rd1000 5 місяців тому +2

      We were talking about Pizza here, deep dish is a garnished bread or tomato soup in a bread bowl, depending where you buy it, but not a pizza. :D

    • @daddymuggle
      @daddymuggle 5 місяців тому

      ​@@h4z4rd1000exactly. Thickness affects the deliciousness factor.

  • @alexzaze1407
    @alexzaze1407 5 місяців тому +7

    Can you teach how to do the instant marker-swap techinique? Does it work with pens aswell?

    • @adipy8912
      @adipy8912 5 місяців тому

      Type "how to blackpenredpen" in the search bar

    • @inmuyataz
      @inmuyataz 5 місяців тому +1

      It does, you just need to rotate it, u just use your index finger to push and use the one above.
      Well at least that's how i do it , i think there's different method of doing it since i just try to copy my friends long ago

    • @alexzaze1407
      @alexzaze1407 5 місяців тому

      @@inmuyataz a video tutorial would be nice for that

    • @adipy8912
      @adipy8912 5 місяців тому

      @@alexzaze1407 He already has a video about it: ua-cam.com/users/shortsgoMm-zD4tKA

    • @adipy8912
      @adipy8912 5 місяців тому

      @@alexzaze1407 He already has a shorts video about it. Search "how to blackpenredpen"

  • @IcyFrost200-eu8sr
    @IcyFrost200-eu8sr 5 місяців тому +21

    I somehow decided to just use my math skills while lying in bed with post nut clarity. It felt nice to do math

    • @davidsantiago7808
      @davidsantiago7808 5 місяців тому

      Play a game of chess before you sleep, it's fun to use your brain before sleeping.

    • @PoKeKidMPK1
      @PoKeKidMPK1 5 місяців тому

      ​​@@davidsantiago7808 then you lose without knowing why to someone who won without knowing why.
      then it didnt matter and now its the morning and your thinking about life after what ever occurs in the day.

    • @davidsantiago7808
      @davidsantiago7808 5 місяців тому

      @@PoKeKidMPK1 or u win, but either way you experience a fun way to work the brain. Unless you're a sore loser you coudl have fun even if you lose, chess is just a game after all. The brain is a muscle, and a lot of people lack hobbies that stretch the brain. I am just saying it is healthy and relevant to the original comment

    • @PoKeKidMPK1
      @PoKeKidMPK1 5 місяців тому

      @@davidsantiago7808 i dont think you do activities like chess often. it doesnt work that way, in even basic actions. googling info like that doesnt either because it creates beliefs.
      internet/supplements vs common good habits and purposeful testing
      worrying about being glorified on a random nights single chess game is also a hilarious self-brought contradiction to the point of learning.

    • @PoKeKidMPK1
      @PoKeKidMPK1 5 місяців тому

      @@davidsantiago7808 you must not do activities like chess often then. it doesnt work that way, in even basic actions. you mind as well tell him to wake up, walk, breath, live life and it would be the same redundant idea. searching info like that doesnt either because it creates a fantasy.
      internet/supplements vs common good habits and purposeful testing
      worrying about whos being glorified on a random nights single chess game is also a hilarious self-brought contradiction to the point of learning.

  • @Exath8630
    @Exath8630 29 днів тому

    I solved it by calculating the second slice's area relative to the first slice. I found that the second pizza is 49/48 of the first slice, which is only 1/48 bigger, yet the price of second pizza is 2/15 more, so the answer is the first pizza.

  • @Zeylo89
    @Zeylo89 6 годин тому +1

    First piece has a bit more crust

  • @francoismusic_
    @francoismusic_ 4 місяці тому +7

    0:24 Bro farted, and thought we wouldn't notice

  • @leonardobarrera2816
    @leonardobarrera2816 5 місяців тому +4

    That is why sellers of pizza never gives you mathematical data for you to buy it in the wrong way
    Hahaha

  • @NoahOliver-rx3mp
    @NoahOliver-rx3mp 5 місяців тому +9

    Hallelujah 🙌🏻!!!!! The daily jesus devotional has been a huge part of my transformation, God is good 🙌🏻🙌🏻. I was owing a loan of $49,000 to the bank for my son's brain surgery, Now I'm no longer in debt after I invested $11,000 and got my payout of $290,500 every month…God bless Mrs Susan Jane Christy ❤️

    • @KleffmanRosenbush
      @KleffmanRosenbush 5 місяців тому

      Hello!! how do you make such monthly, I’m a born Christian and sometimes I feel so down of myself 😭 because of low finance but I still believe God

    • @KontyBierbaum
      @KontyBierbaum 5 місяців тому

      Thanks to my co-worker (Carson ) who suggested Ms Susan Jane Christy

    • @LouisPeters-fw9cg
      @LouisPeters-fw9cg 5 місяців тому

      She's a licensed broker here in the states🇺🇸 and finance advisor.

    • @LouisPeters-fw9cg
      @LouisPeters-fw9cg 5 місяців тому

      After I raised up to 525k trading with her I bought a new House and a car here in the states🇺🇸🇺🇸 also paid for my son's surgery….Glory to God, shalom.

    • @SauredoFevold
      @SauredoFevold 5 місяців тому

      Can I also do it??? My life is facing lots of challenges lately

  • @aydennuula979
    @aydennuula979 5 днів тому

    Now that I'm out of school and see these concepts not in a text book, I can understand it way better. Good work

  • @orangenasa
    @orangenasa 5 місяців тому +1

    The secret is that you want to be the one that offers both of these deals and let me explain why
    if a customer sees two deals they instinctively focus on which one is the better deal and then decide which one to buy. this automatically puts both deals in contrast and the customer will be more tolerant towards the deal that is "better", disregarding that they could potentially be ripped off no matter which one of them they buy because they could both just be overpriced.
    As the one who offers both of these, you can just make both of them overpriced but one a little cheaper than the other one and profit.

  • @FrankBlissett
    @FrankBlissett 2 місяці тому +1

    As you are comparing them, you don't need to figure out the area - it's 6/6 * 1.5 compared to 7/8 * 1.7. Much easier to figure out in your head.

  • @jeskoumm
    @jeskoumm 5 місяців тому +1

    “OP did not mention, the 1.50 pizza uses cheese processed with almond milk from North Korea, whereas the 1.70 pizza uses marinara sauce made with soy from Taiwan.”

  • @JohnMendez-u8d
    @JohnMendez-u8d 2 місяці тому +1

    Just count the pepperonis

  • @randomhubbard3792
    @randomhubbard3792 5 місяців тому

    If math was taught with practical real life situations like this, no one would say they'll never use it outside of highschool.

  • @nekogod
    @nekogod Місяць тому +1

    If you only care about which is a better deal and don't need the actual cost per square inch then you can ignore pi and it becomes 150/(6*6/6) =25 and 170/(7*7/8) =27.76 meaning the smaller slice is better value.

  • @kato4792
    @kato4792 Місяць тому +1

    saw the thumbnail and did it a different way but came to the same conclusion:
    PI*(6^2)*(60/360)*(1/1.50)=12.56 in^2 pizza per dollar
    PI*(7^2)*(45/360)*(1/1.70)=11.31 in^2 pizza per dollar
    Therefore, pizza 1 is the better deal 🎉

  • @iagorocha4814
    @iagorocha4814 5 місяців тому +1

    7" has more pepperoni slices, its enough for me.

  • @piratekit3941
    @piratekit3941 2 місяці тому

    I thought I would never use math like this in HS...and then I joined a D&D group and our DM was my calculus tutor and kept putting a ton of math puzzles into his campaigns. I wanted to be mad, but he ran a good session.

  • @wolkaiserdrake9946
    @wolkaiserdrake9946 2 місяці тому +1

    I am slightly tipsy and when I'm tipsy I like doing math, UA-cam recommend this, I am happy

  • @MissesWitch
    @MissesWitch 2 місяці тому

    I love this teacher using real life examples!
    In class we're always taught made up examples, But when it's real, You really feel it! ❤

  • @BlondeTiger
    @BlondeTiger 12 днів тому

    I could just see with my eyes that a one inch gain in length is not worth the multiple degrees you loose for more money, but thanks for proving it with a long complicated process that I will never have time to do while I'm ordering pizza in a restaurant.

  • @lobbyrobby
    @lobbyrobby 4 місяці тому

    Just like high-school I quit paying attention pretty much right away and just waited for the answer. The original thought was the $1.50 slice

  • @Closer2Zero
    @Closer2Zero 9 днів тому

    I’m glad that after all these years, I was still able to eyeball which slice was bigger I just didn’t break out of calculated it to than unit price them

  • @royale1223
    @royale1223 14 днів тому

    Size is proportional to r^2 and the angle and. So ratio is 36*60 : 49*45, simplified into 36*4: 49*3 or 144:147. The second piece is slightly bigger. Since the price differs significantly, order the first pizza.

  • @Mike23443
    @Mike23443 5 місяців тому

    I can't do any of these calculations but my pizza instinct told me in 0.0001 seconds that the 1.50 was a better deal.
    Ergo
    You don't actually need the math, it's just a ruse to confuse you into doubting your pizza instinct.

  • @byrontheusurper6505
    @byrontheusurper6505 Місяць тому +1

    Lemme try to solve this from my mind, i'm trying to de-rust my maths: So you calculate the area of the whole pizza with 2pir², r being the inch count, then you multiply that with the radius of the slice/360° to get the slices' area and then divide that by the Price to get the ratio of area to Price, whichever one's bigger is the winner. Edit: alright, I misremembered the circle area formula and did the ratios the other way round (which does not matter if I'm correct)but otherwise I got it! I mean I'm technically at college level (although I've missed a disproportionate ammount of maths classes and haven't done a single test right so i might be rusty) so it shouldn't surprise me but it's nice to know I can still do it and have fun doing so!

  • @dutchchiefofministry1983
    @dutchchiefofministry1983 Місяць тому

    It took me a while to notice but the slide of hand going from the red marker to the blue one is awesome

  • @William-Sunderland
    @William-Sunderland 5 місяців тому

    Get area for both complete pizzas, as 60° is a 6th of a complete pizza A and 45° is a 8th of a complete pizza B, you can get both portion areas by dividing the area you need from a complete pizza, then its only a matter of dividing each area by its price to get the area of each of both pizzas that represents 1$, the higher value per $ is the better deal.

  • @quinnbell2388
    @quinnbell2388 5 місяців тому

    Since pi is in both areas, it may be helpful to consider it as part of the units. Assuming I did my math right, I found slice a to have an area of 6 pi in^2 and slice b to have an are of 6.125 pi in^2. Considering the price per slice, that resulted in $0.25 per pi square inches for slice a and about $0.28 per pi square inches of slice b which seem like more useful numbers in this context

  • @cubicinfinity2
    @cubicinfinity2 5 місяців тому

    It's cool that just looking with my eyes I could make the correct guess that the left slice was a better deal. There is also the factor of edge crust vs toppings, but it's not enough in this case to make the larger slice better.

  • @946towguy2
    @946towguy2 2 дні тому

    We only need to find which slice is less per unit of area.
    Radius squared times Pi is formula for a circle.
    Both slices use pi and inches and dollars, so cancel out Pi and remove like unit descriptors. 1.5 and 1.7 are numerators.
    a circle has 360 degrees, 60 deg and 45deg are 1/6 and 1/8 circle respectively.
    60 deg, 6 radius means 1/6*6*6, cancels to just 6
    45 deg, 7 radius means 1/8*7*7 or 49/ 8 or 6 1/8 or 6.125
    Compare which is smaller: 1.5/61.7/6.125
    Multiply both numerators by 4 to simplify: 1.5*4=6, 1.7*4=6.8
    6/6=1, 6.8/6.125 is >1
    1

  • @SillyOrb
    @SillyOrb 4 дні тому

    A simpler variant with a somewhat more intuitive answer is:
    Given
    360 / 60 = 6
    360 / 45 = 8
    We compute
    6 x 6 / 6 / 1.5 = 6 / 1.5 = 4
    7 x 7 / 8 / 1.7 = 6.125 / 1.7 = 3.6
    The first number is bigger than the second, therefore it says that the first slice has more pizza per unit of currency.
    The results aren’t real quantities (area in this case) and this simplification is only useful for direct comparisons. So, it’s not meant for real math exercises or measurements, but when comparing prices in your head at a store. It’s the rough total divided by how many pieces it was cut into per your currency. This helps when maximising the amount of actual pizza for your money (with one fewer division when buying a whole pizza), as most places have several sizes at different price points and sometimes the medium option is the best, sometimes the small is the best and at other times the big is best. Cheers.

  • @Me_Caveman
    @Me_Caveman Місяць тому

    This is like physics without friction. You still have to face the health consequences.

  • @SpiceCh
    @SpiceCh 5 днів тому

    In a real-world scenario, you'd also have to factor in the attractiveness of the crust. The cheaper piece has more crust while the more expensive piece gives you more toppings, which could justify the price premium, especially if you're not a crust enjoyer.
    Jokes aside, this is a great demonstration of math on a level that kids would be able to understand as well.

  • @liherx
    @liherx 5 місяців тому +1

    Taking into account the extra pizza you receive buying the right one, it should cost only 3 cents more than the left one. However, the right one has less edge, so some people may like it more

  • @carlhartmann5925
    @carlhartmann5925 Місяць тому

    There’s a much easier way to do this. Seeing as the left one is part of a circle splitt into 6, and the other is part of a circle split into eight you can just calculate the area of the whole cirle and divide by 6 and 8 respectively to get the are of the slice.

  • @fvw1187
    @fvw1187 5 місяців тому

    Imagine doing the hard part of this problem then not dividing the price correctly.

  • @meppeorga
    @meppeorga 3 місяці тому

    Did the math in my head, did it wrong, forgot about r^2 and reached the correct answer anyway.
    boom, quick maths

  • @Syrahl696
    @Syrahl696 2 місяці тому

    By approaching the problem slightly differently, I was able to work it out in my head after being reminded of the formula. You can simplify the formula for the first one to 1/6 * pi * 6^2, and work out in your head that the fraction cancels out the exponent and it comes to 6*pi. Doing the same thing with the second slice gets 1/8 * pi * 49, rearrange to 49/8 * pi, or 6 + 1/8 * pi.
    Then, you can multiply the prices by 4. The first slice is $6 for 6*pi units of area, the second is $6.80 for 6.125*pi units of area. From there, it's obvious the first one is the better deal.

  • @IISourAyyII
    @IISourAyyII 5 місяців тому

    see this is a good math teacher, it all makes sense, down to the marker colors, red = variable, black = constant

  • @ollllj
    @ollllj 2 місяці тому

    A LOT of pizza deliveries sell a pizza of 2x the radius for 2x to 3x the cost (much closer to 2x) , while it has almost 4x as much pizza, because radius gets squared.

  • @Darkell64
    @Darkell64 4 місяці тому +1

    If the number of pepperoni is the same in both, buy the cheaper one, I get it.

  • @GIMMETHELOOTNOW
    @GIMMETHELOOTNOW 4 місяці тому +1

    These 4 teenagers named Michael Angelo, Leo, Donny & Raph took a pizza 😂😂😂😂

  • @crasite
    @crasite 5 місяців тому +1

    Regarding the crust. If the crust is longer than ~ 1.6 Inches then the tall one would be cheaper

  • @MrLycan1995
    @MrLycan1995 3 хвилини тому

    You ignored the topping to dough ratio tho. The 60° slice has more crust on if we assume both slices have the same crust width therefore bringing the topping to dough ratio down which is paramount in the pizza value formula.

  • @I_Willenbrock_I
    @I_Willenbrock_I Місяць тому

    Calculate the surface of the circle based on the radius.
    The surface of the 6 inch decided by 6 (because a full circle has 6 pieces)
    Compare to the 7 inch version, decided by 8 (because 8 pieces).
    Highest number wins. Assuming that both pizzas are equally thick.

  • @Ebola419
    @Ebola419 День тому

    The second slice in the image has more pepperonis on it. That fact alone makes the second the better value

  • @thgeremilrivera-thorsen9556
    @thgeremilrivera-thorsen9556 3 місяці тому

    The big glass in his argument is that he neglects to take into account that the left pizza slice has a higher crust-to-topping ratio. I feel like this should be factored in.

  • @KozelPraiseGOELRO
    @KozelPraiseGOELRO Місяць тому

    I am somewhat dissapointed, I expected integrals of polar functions.
    You know, the
    r1 = 6, 0

  • @seantaft3853
    @seantaft3853 5 місяців тому

    These are the examples needed to teach math to students.
    It helps them understand a better deal, something they'll likely want to know. Plus, pizza.

  • @huntergrant2011
    @huntergrant2011 3 місяці тому

    You have to remove half an inch from both slices to account for the crust since the toppings is the part you are worried about

  • @sofishticated289
    @sofishticated289 5 місяців тому +1

    Maybe the Second is the better deal, because you get less crust which has no topping. The topping is the valuable part of the Pizza ;)

  • @thenameless422
    @thenameless422 4 місяці тому

    This is the dude who's already computing for his birthday cake's circumference on his 1st birthday my mom told me about when I was growing up.
    Jokes aside, thank you for contributing to society in a way most people would relate or be interested with which is food. With the newer generation being more and more technologically dependent, manual computation just gets thrown aside in favor of advanced calculators or would take things at face value like going for the 7" slice.

  • @kvatreo
    @kvatreo 5 місяців тому

    Simple: Price ratio is 15:17 White the pepperoni ratio is 7:9 or for easy comparison 14:18, so the 7” slice is clearly the better offer!

  • @jimi02468
    @jimi02468 5 місяців тому

    It's the type of problem that takes you ten seconds to solve. Just write the expression 1.5/((60/360)*pi*6^2)-1.7/((45/360)*pi*7^2) into a calculator and notice that if the answer is a negative number, the left pizza is the better deal and if positive then the right pizza.