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

We have two slices of pizza. One is with a radius of 6 inches and a central angle of 60 degrees while the other is with 7 inches and a central angle of 45 degrees. The first slice costs $1.50 and the second one costs $1.70. Although the prices aren't realistic (unless you are in New York because there are $1 slices), which slice is a better deal?
Original post on Reddit: 👉 / tmmczrfjt2
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#math #algebra #mathbasics

[@bprpmathbasics]

1 divided by 0 (a 3rd grade teacher & principal both got it wrong), Reddit r/NoStupidQuestions kzbin.info/www/bejne/jXrCooN4hs19ia8

[@mekaindo]

"NoStupidQuestions"

[@shelby-r1e]

How dare you not factor in the crust.

[@Wunderschon657]

😇😇😇😇😇

[@Wunderschon657]

dneme 123

[@Wunderschon657]

😇😇😇😇😇

[@qwertek8413]

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

[@dannyyeung8237]

Yes I knew about it on 29 March 2024

[@imveryangryitsnotbutter]

Mmm, πz²a.

[@rujon288]

cook

[@retardigrade69]

This touched my brain in a very funny way

[@Ahmed-kg2gf]

​@@imveryangryitsnotbutter π is pi and z² is zz

[@Sockerrus]

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

[@deivisnx]

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

[@sergio73master1]

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]

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

[@rebane2001]

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

[@josevictorribeirolisboa7576]

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

[@richardhole8429]

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

[@sureshmukhi2316]

😂

[@perrinromney4555]

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

[@keescanalfp5143]

​@@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]

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

[@facesmelt9903]

Yeah once I heard pi I started eating the whole pie

[@daroxes6399]

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

[@brownfamily1892]

This is the only correct method

[@eminkilicaslan8945]

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

[@dark6.6E-34]

Dont forget the pictures on display can be misleading.

[@0x1EGEN]

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]

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

[@wobaguk]

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

[@theodoremurdock9984]

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]

​@@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]

​@@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]

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]

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

[@marcush4741]

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]

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

[@marcush4741]

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

[@GG-mb9rr]

Or dipping sauce

[@kylen6430]

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]

⁠@@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.

[@GoldenLeafsMovies]

Bro has the quickswap skill unlocked for switching markers.

[@danny1103]

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]

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]

​@@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]

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]

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

[@sabin97]

@@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.

[@realDonaldMcElvy]

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]

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

[@ramennoodle2085]

Crust is the best part.

[@highviewbarbell]

​@@Verxinnones worth is determined by their girth

[@vincentlamontagne7639]

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

[@patrickd9551]

@@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 ;)

[@davidellis1929]

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

[@3dbyeb971]

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

[@jamesharmon4994]

Eat the crust!! 😅

[@Snaproductions]

the frust is good

[@MrSparkefrostie]

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

[@janb.3600]

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

[@phiefer3]

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.

[@Zufalligeule]

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]

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

[@mawillix2018]

@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]

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

[@SunDry_Marchy]

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]

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

[@Nomimasu]

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]

i did the same thing

[@user-vc2yq4mm6t]

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

[@OrangeC7]

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]

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]

@@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.

[@danteeightsix9069]

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

[@Wise_That]

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

[@oliverschell7014]

Yes, but 13 % more expensive.

[@GamerNineSix]

But also less crust

[@lupolinar]

Also more salami slices

[@Zhcwu]

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

[@0x0404]

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]

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

[@theNaluK]

This is exactly what I was thinking!

[@GG-mb9rr]

Not if you have dipping sauce for the crust

[@Zakon213]

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

[@macromite3758]

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

[@neilgerace355]

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

[@jabbawookeez01]

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

[@taito404]

Ooh. I like that thinking. Very creative

[@ailst]

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]

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

[@jamesharmon4994]

​@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. 😅

[@jamiew7805]

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]

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

[@zeroone8800]

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

[@MikehMike01]

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

[@msolec2000]

Also the 360º in the denominator cancels out

[@zeroone8800]

@@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]

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

[@57thorns]

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

[@davidellis1929]

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]

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

[@johnpaullogan1365]

@@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]

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

[@snestah]

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.

[@lool8421]

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

[@Ramu-10]

As a lot of people here have pointed out, the crust is also important. In addition to that, the enjoynment of the crust matters too. Lets label that 'c'. The enjoynment of the rest would be 1 as in 100 %. Assume that the crust is 1 inch. The wide pizza has an area of A_wp = 1/6*π*5^2 = 25π/6 and the tall pizza has an area of A_tp = 1/8*π*6^2 = 9π/2 Crust is the remaining area. For the wide A_wc = 1/6*π*6^2 - 25π/6 = 11π/6 and for the tall A_tc = 1/8*π*7^2 - 36π/8 = 13π/8 Total food/enjoynment you're getting is f_w = (25+11c)/6 f_t = (36+13c)/8 Calculating the price per dollar for each gives us p_w = (25+11c)/6/1.5 = (25+11c)/9 p_t = (36+13c)/8/1.7 = (36+13c)5/68 Finally, lets see how much the crust enjoynment needs to be for each choice. (25+11c)/9 = (36+13c)5/68 68(25+11c) = 45(36+13c) 1700+748c = 1620+585c 80+163c = 0 c = -80/163 ~ -0.49 As we see, since the enjoynment needs to be a negative number (0 means no crust basically) so regardless of whether you like crust or not, you should get the wide piece.

[@robertonoz616]

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]

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]

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]

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.

[@ironfoot1938]

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]

That’s how I did it.

[@TheFantasticWarrior]

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

[@chrisschack9716]

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]

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

[@Anthony_Marquis]

In this particular example, as long as one knows that a circle is 360° in totality, one doesn't even necessarily need to know the (pi)(r^2) formula in order to figure out the solution. 60° = 1/6 of 360° and 45° = 1/8. 1/6 of the 6-inch-side is 1/1 (or 8/8), and 1/8 of the 7-inch side is 7/8. Now, without doing any (pi)(r^2) calculations, we can already see that they are selling the 8/8-proportion slice for $1.50 which is both larger (in proportion) and cheaper than the 7/8-proportion slice which is being sold for $1.70. So one doesn't even have to complete the extra-step of dividing the two different proportions by their correlating prices to know that the cheaper slice also has a larger area-for-cost-ratio making it the obvious choice for anyone who wants to "get more bang for their buck".

[@charlesxavier1904]

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]

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]

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]

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.

[@albertyu750]

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.

[@nimiugn]

I'm glad we can instinctively tell that the 2nd one is slightly larger but not that large compared to the price difference

[@gildedbear5355]

Humans are, generally, pretty bad at comparing tall and thin things with short and wide things. Though it's worse when dealing with volume since there's an extra dimension involved.

[@sabin97]

i couldnt instinctively tell. i had to do the calculations. i dont trust "instincts" or "common sense". i trust numbers.

[@DEMERN]

when i figured it out, i just left pi out of the area equations. the ratio between the two areas is still the same with or without it, but it meant i was able to do it all without a calculator. well, except for the very end when i had to calculate 6.125 divided by 1.7

[@fifiwoof1969]

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]

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]

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]

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

[@JeffPenaify]

plus as a high school dropout with terrible math skills, but knows pizza, the 60 degree cut will yield more crust per $/ square inch vs the 7 inch slice at 45 degrees.

[@mikefochtman7164]

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]

Yeah thickness is important as well

[@shaurryabaheti]

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

[@werdwerdus]

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]

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]

​@@h4z4rd1000exactly. Thickness affects the deliciousness factor.

[@andrewshiff2004]

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.

[@rpfour4]

I dunno. The 2nd pizza has more pepperoni.

[@hemandy94]

That's why it is 20 cents higher

[@werdwerdus]

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

[@Jaymunnie]

There are also other variables to consider, like the width of the crust, the overall thickness of the pizza slice, the weight of the toppings.

[@R3LI2UI]

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]

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

[@R3LI2UI]

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

[@werdwerdus]

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

[@jeskoumm]

“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.”

[@nicolastorres147]

Calculator isn't necessary to compare both since both share the factor of pi/360° which you can ignore and compute the rest

[@huntergrant2011]

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

[@alexzaze1407]

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

[@adipy8912]

Type "how to blackpenredpen" in the search bar

[@inmuyataz]

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]

@@inmuyataz a video tutorial would be nice for that

[@adipy8912]

@@alexzaze1407 He already has a video about it: kzbin.infogoMm-zD4tKA

[@adipy8912]

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

[@jackmacziz6140]

A true mathematician would know that In the 4.5 minutes it took to figure out which pizza is cheaper and save 20 cents, you could’ve just worked an extra 4.5 minutes for federal minimum wage and had earned and extra 54 cents

[@IcyFrost200-eu8sr]

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

[@davidsantiago7808]

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

[@PoKeKidMPK1]

​​@@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]

@@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]

@@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]

@@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.

[@lobbyrobby]

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

[@leonardobarrera2816]

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

[@twylanaythias]

Or... ~ 1/6 Pi 6^2 = 6 Pi ~ 1/8 Pi 7^2 = 6.125 Pi Option 1 : (6 Pi)/$1.50 = $0.25 per Pi ~ To provide the same value, the 7" slice would cost $1.533; as it actually costs $1.70, the 6" slice is clearly the superior value. Option 2 : $1.50 × 4 = $6 (making $ = Pi) ~ $1.70 × 4 = $6.80, which is clearly greater than 6.125; once again, the 6" slice is clearly the significantly better value. As this question is a simple comparison (which is the better value), all we need is a basic ratio between size and price. We don't even need to do precise calculations... Using Option 1, we know that the extra $0.20 at $0.25/Pi should provide 0.8 Pi more pizza for the same value vs the 0.125 Pi difference. There's no need to go any further in order to determine that the 7" slice offers less value than the 6" slice.

[@yurenchu]

"... the 7" slice offers less value than the 6" slice." Judging from the image, the 7" slice offers about 8.5 round pieces of pepperoni while the 6" slice offers about 7 round pieces of pepperoni, so the 7" slice offers about 22% more pepperoni, for just a 13% higher price.

[@NoahOliver-rx3mp]

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[@KleffmanRosenbush]

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[@KontyBierbaum]

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

[@LouisPeters-fw9cg]

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

[@LouisPeters-fw9cg]

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]

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

[@Momie_et_Masque]

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

[@cubicinfinity2]

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.

[@jarnovanderzee2469]

(7^(2)÷8)÷(6^(2)÷6) ≈ 1.021, so the long slice is aproximatly 2.1% bigger, but the price, is way bigger than that so i'd choose the phat slice.

[@GIMMETHELOOTNOW]

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

[@thgeremilrivera-thorsen9556]

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.

[@EricHeran]

Proud that I worked this exactly the same way before watching it. I worry about forgetting things as I age, I'm happy to report I may not use it as much as I would like, but I still can!

[@ConTrollFM]

The $1.70 has less crust and looks like more pepperoni slices in thumbnail, that's additional value

[@William-Sunderland]

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.

[@user-xp8tc2yl8j]

But the 60° slice has more crust you have to factor that out.

[@jimi02468]

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.

[@m.h.6470]

Solution: Left is 1/6 of the full circle of π*6², as 60° * 6 = 360° Right is 1/8 of the full circle of π*7², as 45° * 8 = 360° Since both sides have π, we can cancel it. Left we have 6²/6 = 6 Right we have 7²/8 = 49/8 = 6 + 1/8 Divide both sides by 6, we get Left = 1 Right = 1 + 1/48 Multiply both sides with 1.5 Left = 1.5 Right = 1.5 + 1.5/48 = 1.5 + 3/96 ≅ 1.5 + 3/100 = 1.53 So the left side has better value, as the right side should only cost ~1.53, not 1.70

[@seantaft3853]

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.

[@chicopluma]

Mathematician: fair enough Engineer: you forgot the pizza's thichness, crust and ingredients ammount Phisicist: bro, what's the brand

[@thechatter7102]

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

[@runningkeddy]

Let’s say $1.5 is the standard price. To convert the left pizza to the right, $1.5*6=$9 since it’s 1/6 of a round pizza. Scale the size up of a 2 dimension shape, it will be $9*7*7/6/6=$12.25 . 45 degree is 1/8 of a round a round pizza so $12.25/8. Therefore the right one should cost $1.53125 according to the standard.

[@Tobarius]

I think the teacher wanted the answer with pi as a factor and using the unit square inches per dollar, because then the first slice would be 4πin²/$ against ~3.6πin²/$.

[@michaelsullenberger6730]

Ah yes, and as your measuring the gas station pizza trying to figure out which one has an extra bites worth, the person behind you in line buys both of them and a pack of cigarettes.

[@Tzizenorec]

You don't need to think about the value of Pi when you're comparing two values like this. The volume of the slice on the left is 60*6^2*(some constant). The volume of the slice on the right is 45*7^2*(that same constant). Divide both sides by the unknown constant, divide both sides again by 15 degrees, and you come up with the very easy comparison between 4*6^2 and 3*7^2. You can do that in your head.

[@RealGhoda]

Quick mental maths, area proportional to radius squared * fraction of the circle, and I just divide by the price to find smin related to area/dollar 6^2*1/6 = 6; 6/1.5$ = 4 7^2*1/8 = 6.125; 6.125/1.7 is less than 4 (1.7*4 = 6.8) first option better (I am indeed an engineering student)

[@svennoren9047]

I did it the same way. I've been an engineer for 40 years.

[@eipiwau]

As the area of a circular sector grows linearly in the angle and quadratically in the radius, you can see that the second slice would have to cost 1.50*(45/60)*(7/6)^2 = $1.53, but it costs more so the first one is better value.

[@FurbleBurble]

I wish more people took stuff like this seriously. Knowing how to make good use of price/unit can potentially save you hundreds of dollars a month on groceries.

[@gamadays2316]

Easier approach: first Pizza is 1/6 and second is 1/8 so whole pizzas cost: 9$ and 13,6$. r^2= 36 and 49. 9/36=0.25 13,6/49=0.27 smth. Therefore left is cheaper.

[@itsamemario6588]

Also of critical value is computing the dollars per inches squared of cheese/ topping area, assuming crust is 0.5 inches offset from the edge for either pizza. The 6" pizza is roughly 9.5 cents per "yummy" square inch. The 7" pizza is roughly 10.2 cents per yummy square inch. Still better to go left, but it's even closer with this evaluation.

[@battle00333]

Another neat approach to this is to look at scale factor. The 60deg pizza is, 60/45 x 36/49 times bigger/smaller than the 45deg pizza. (smaller) Which comes out at about 2.08% less area. But the price of the smaller pizza is 13.33% cheaper. In other words, the 45deg pizza, costs 13.33% more currency, for only 2.08% more area.

[@jesss2830]

"ah, but what of the crust-to-pie ratio?" me at 4am

[@redslate]

This is important.

[@RexxSchneider]

Area of a sector is proportional to radius squared and the angle. The units don't matter if we are just making a comparison. So 6 * 6 * 60 / 1.5 = 1440 area units per dollar And 7 * 7 * 45 / 1.7 = 1297 area units per dollar The first one is better value and it doesn't take almost 5 minutes to work out.

[@Jeremo-FD]

Assuming equal thickness, the left one gives you 12.56 pizza inches per dollar & the right one gives you 11.31 pizza inches per dollar.

[@lucasrfma]

I compared the slices before watching the videos by simplifying the calculations. Since it's area calc, I squared the radius. And then the angle will determine a proportion, since it was 60o and 45o, I multiplied the first one by 4 and the second by 3. So: 4 x 6^2 = 144 w/e units for $1.5 3 X 7^2 = 147 w/e units for $1.7 The $1.50 slice is better

[@Mcdfr123]

This is why I'm home educating my child. You don't need shit like this in the UK, the price per 100g or 100ml is mandatory on most stuff.

[@Manker00]

The Area of a circle: A(circle) = pi * r^2 A full Circle with 360° = 1 => 45° and 60° are 0.125 (45/360) and 0.1667 (60/360) Let pi approximately equal 3.14159 A(60° & 6in) = 3.14159 * 36 * 0.1667 = 18.85 A(45° & 7in) = 3.14159 * 49 * 0.125 = 19.24 Area of respective pizza divided by respective cost: 18.85 / 1.5 = 12.5667 19.24 / 1.7 = 11.32 => You get ~11% (12.5667 / 11.32) more surface area per dollar if you choose the 60°, 6-inch pizza slice versus the 45°, 7-inch slice.

[@fvw1187]

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

[@protojager]

My math skills are so bad that I got as far as figuring out that one pizza was $9 and the other was $13.60 without knowing how to apply that information or if it was even relevant.

[@DizzySaxophone]

The 7" has more pizza for less crust though. That should definitely be a factor. Not sure it'll make up the difference, but for those that aren't crust fans, might be worthwhile.

[@quinnbell2388]

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

[@badboybs98]

You can do this without using pi. 60*6 =360 45*7= 315 The first pizza is 15% bigger roughly. And cheaper. Unless you want exact numbers. This can be good for quick maths.

[@randomusernameCallin]

From a Programming side, I recomment to see if you are comparing two values that requires Pi to find then leave the Pi to the end and see if you can ignore Pi. The goal is not to find the cost per area and to find the smaller cost per area. So the 60 degrees slice would be (1.50/6 or 0.25) * 1 / Pi and 45 Degree slice become (1.70 / 6.125 or 0 .27755) * 1/Pi since Pi is constant you just need to pick the smaller number which is 60 degree slice with 0.25 * 1/Pi.

[@cyalknight]

60° makes up 1/6th of 360. Find the area of a circle with a radius of 6 inches and then divide by 6. 45° makes up 1/8th of a circle. The radius is now 7 inches.

[@celesteamour]

The better deal for me is always going to be the more narrow slice. I hate wide pizza slices almost as much as I hate a thick crust. I will pay more to not be annoyed 🍕

[@crasite]

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

[@rendynurmansyah4626]

The thing is medium and large pizza usually use same amount of dough, so medium is thicker and large is thinner And the thinner one usually taste better

[@earthwyrm6756]

Not true @Domino's.

[@julkkis666]

(60÷360)(6×pi) > (45÷360)(7×pi) That is, if i remember the usage of pi correctly. The cheaper pizza has an area of 3. Something and the more expencive is 2. Something.

[@als2cents679]

Dollar per area comparison 1.5 / (pi * 6^2 * 60 / 360) : 1.7 / (pi * 7^2 * 45 / 360) 15 / (36 / 6) : 17 / (49 / 8) 15 / 6 : 136 / 49 735 : 816 So first option is better.

[@ManofTroy81]

You will never have to make this choice in a restaurant. They're only going to sell pizza slices in one size, and that is normally the larger pizza they offer.

[@sofishticated289]

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 ;)

[@IISourAyyII]

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

[@jacklawsen6390]

The 7" radius piece is a little bigger, but still slighty more expensive per square inch.

[@Lisan_ps]

"Lemme get a slice of pizza" "Sure, which one?" "Hold up lemme get my calculator"

[@kvatreo]

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!

[@SunDry_Marchy]

Disregard 1/360 (keep the angles) and the pie number. They both repeat anyways, unique variables only should be in the final equation

[@meyes1098]

I prefer to do the area divided by the cost, because it basically tells you how much area of pizza you get for a dollar. In the first case it's 18.83/1.5 = 12.55 in^2 per dollar In the second case it's 19.25/1.7 = 11.32 in^2 per dollar The first case gives you more area per dollar, hence why it's better. This way also keeps it in line with how our caveman brains work, in that we consider the bigger number to be better :)

[@michaeledwards2251]

The simplest way to view the problem is to use a scaling factor. 1. Assume the pizza's are equal thickness : inspection is assumed sufficient 2. The area is proportional to the square of the radius. 3. Each pizza is a part of a whole. 4. For the case (left) r^2 = 36 (radius = 6), divided by 6, (60 degree angle) giving a scaling factor of 6. For the case (right) r^2 = 49 (radius = 7), divided by 8, (45 degree angle) giving a scaling factor of 6 + (1/48) 5. For the prices of $1.50 and $1.70 respectively, the higher price is approximately 1/8 greater than the lower. Conclusion A . The pizza are the same area within the experimental bounds of noise : measurement inaccuracy is greater than 1/3 % : area is a red herring ((1/48) divided by 6, the scaling factor, gives a difference of (1/288)) B . If they are the same quality, only the price is significant C . Pick your preference, price for consumption, vice versa for charity.

[@Revixter]

As a kid I would always win those school competitions where you'd guess how many beans were in a jar. I can look and just tell the left one, at that value, is better without doing any math. Area is almost identical, the price pushes it clearly in favor of the left one. I feel this problem would be a lot tougher for me to judge without the difference in price value.

[@red2503]

I always calculate if one large pizza is cheaper per area than two small pizzas to determine what to buy