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

  1. Oct 18, 2013 #1
    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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  3. Oct 18, 2013 #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?
     
  4. Oct 18, 2013 #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.
     
    Last edited: Oct 18, 2013
  5. Oct 18, 2013 #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.
     
  6. Oct 18, 2013 #5

    lisab

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    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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