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Math Help - digit integer problem

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    digit integer problem

    What two-digit integer is six times the sum of its digits?
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    Super Member Matt Westwood's Avatar
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    Quote Originally Posted by sri340 View Post
    What two-digit integer is six times the sum of its digits?
    Solve this by setting up the equation:

    10a + b = 6(a+b)

    where a and b are the number's two digits.

    There's only a limited number of integral solutions, and you'll (probably) find that only one of those has both a and b in single digits.

    Give it a play, see what happens.
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  3. #3
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    Quote Originally Posted by sri340 View Post
    What two-digit integer is six times the sum of its digits?
    If xy is the two digit number and x+y is the sum of the digits:

    10x+y = (x+y)6
    10x + y = 6x +6y
    4x = 5y

    Only two numbers satisify that
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