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Ridiculous Math Problems

dam.brown.edu

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Re: Ridiculous Math Problems

#2

Post by dan-robertson »

A ridiculous problem I remember seeing was approximately this one:

  a/(b+c) + b/(a+c) + c/(a+b)=896.
  a,b,c positive integers
I think it probably used random symbols instead of letters and didn’t have the integer requirement. Indeed if you allow real numbers or 0 then it is easy to find a solution. I think it didn’t go particularly viral because it was too hard. I think there’s a slightly easier version if you replace 896 by 16.

Re: Ridiculous Math Problems

#3

Post by contravariant »

dan-robertson wrote: post #2

A ridiculous problem I remember seeing was approximately this one: a/(b+c) + b/(a+c) + c/(a+b)=896. a,b,c positive integers I think it probably used random symbols instead of letters and didn’t have the integer requirement. Indeed if you allow real numbers or 0 then it is easy to find a solution. I think it didn’t go particularly viral because it was too hard. I think there’s a slightly easier version if you replace…

The version I first saw used '4' instead of '896'. Which frankly made the answer large enough that no reasonable amount of brute force could find it.

A good write up can be found here: https://www.quora.com/How-do-you-find-the-positive-integer-s...

Re: Ridiculous Math Problems

#4

Post by kens »

contravariant wrote: post #3
dan-robertson wrote: post #2

A ridiculous problem I remember seeing was approximately this one: a/(b+c) + b/(a+c) + c/(a+b)=896. a,b,c positive integers I think it probably used random symbols instead of letters and didn’t have the integer requirement. Indeed if you allow real numbers or 0 then it is easy to find a solution. I think it didn’t go particularly viral because it was too hard. I think there’s a slightly easier version if you replace…

The version I first saw used '4' instead of '896'. Which frankly made the answer large enough that no reasonable amount of brute force could find it. A good write up can be found here: https://www.quora.com/How-do-you-find-the-positive-integer-s...

That is an amazing, detailed explanation. (Don't be fooled by the quora location.) Spoilers: the solution to the equation is 80-digit numbers, which can be obtained by using elliptic curves, which the link explains in detail.

Re: Ridiculous Math Problems

#8

Post by praptak »

My math teacher used to give us silly problems like how long will it take the raising water level to reach the top step of a ladder hanging down from a ship. It trained us not to apply formulas blindly.

Re: Ridiculous Math Problems

#9

Post by murgindrag »

There's a difference between a ridiculous math programs (which are often amusing) and incorrect ones (for example, adding different units, or absolute units rather than relative ones).

The article mixes the two.

One type is funny and clever.

The other type reinforces misconceptions and is damaging to students.

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