How long does it take to make homework that comes out even, when there

  • Thread starter Tyrion101
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  • #1
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I'm starting to get to a point where the numbers are getting sometimes well beyond 3 digits in length and, I'm constantly amazed at the fact that there are usually no decimals anyplace in the actual problem, and I was wondering how long does it take to find questions that don't have decimals in the problem?
 

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  • #2
phinds
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I don't see why it should take any time at all. How hard can it be to make up problems that have integer solutions?
 
  • #3
collinsmark
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If the problem involves right triangles (utilizing the Pythagorean therem, c2 = a2 + b2) then it ends up pretty easy if the triangles are 3-4-5 triangles (52 = 32 + 42).

You can also scale the 3, 4 and 5 by any constant and it still works out. For example, let's multiply them all by 123.

c2 = 3692 + 4922.

Solve for c.
 
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  • #4
AlephZero
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A good way is first decide what you want the answer to be, then work backwards to find the numbers in the question.
 
  • #5
lisab
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I don't see why it should take any time at all. How hard can it be to make up problems that have integer solutions?

Not very hard for those who can easily solve them forwards and back. But for someone first learning, it's an interesting observation. I wonder how many students are shocked the first time they get an answer that has a digits after the decimal, and realize it's a correct answer!
 

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