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Math Help - Two digit number divided by sum of digits etc.

  1. #1
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    Two digit number divided by sum of digits etc.

    If a 2 digit number is divided by the sum of its digits the result is 6 with a remainder of 6.If the same number has its digits swapped ( if it was 23, it becomes 32) and gets divided by the difference of its digits the result is 23.What's the number?



    Could anyone please help me solve this problem with an equation system with 2 unknowns. I would really appreciate it.
    Last edited by mr fantastic; March 2nd 2011 at 04:49 PM. Reason: Re-titled.
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  2. #2
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    Digits are "a" and "b". You must remember how the base 10 positional system works.

    "If a 2 digit number is divided by the sum of its digits the result is 6 with a remainder of 6"

    \frac{10\cdot a + b}{a+b} = 6 + \frac{6}{a+b}

    More simply, since a+b is NOT zero

    10\cdot a + b = 6(a+b) + 6

    Let's see what you get for the other.
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  3. #3
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    I think I tried solving it this way, but for some reason it did not work.
    Guess I'll try again. Thanks for the reply.
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  4. #4
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    Will the second one be
    (10b + a) : ( b - a ) = 23
    Last edited by Probability1; March 2nd 2011 at 09:09 PM.
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  5. #5
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    Quote Originally Posted by Probability1 View Post
    Will the second one be
    (10b + a) : ( b - a ) = 23
    I presume you mean \frac{10b+ a}{b- a}= 23 which would be the same as 10b+ a= 23(b- a). That would be correct if b> a. If a> b, it would be \frac{10b+ a}{a- b}= 23 or 10b+ a= 23(a- b). Try solving each of those (with 10a+ b= 6(a+ b)+ 6 as the second equation) and see which is correct.Of course, a and b must be integers between 0 and 9.
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  6. #6
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    Solved it.
    The correct one is 10b + a = 23 ( a- b )
    The answer is 96.
    Thanks for the help.
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