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Math Help - I have a question.

  1. #1
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    I have several questions.

    a is positive integer and b<13,


    \dfrac{a.b-b}{a}=7

    What is biggest value of b?
    Last edited by OPETH; August 11th 2008 at 05:59 AM.
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  2. #2
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    Quote Originally Posted by OPETH View Post
    a is positive integer and b<13,


    \dfrac{a.b-b}{a}=7

    What is biggest value of b?
    \frac{ab-b}{a}=7 re-arranges into b = \frac{7a}{a-1}.

    The graph of b versus a is a hyperbola. Draw a graph and you'll see that the largest value of b that satisfies b < 13 and a is a positive integer is b = 21/2 corresponding to a = 3.
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  3. #3
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    b = \frac{7a}{a-1}


    and

    if a=8

    b = \frac{7.8}{8-1} ,

    b = \frac{56}{7}

    b = 8

    Thank you help.
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  4. #4
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    Quote Originally Posted by OPETH View Post
    b = \frac{7a}{a-1}


    and

    if a=8

    b = \frac{7.8}{8-1} ,

    b = \frac{56}{7}

    b = 8

    Thank you help.
    So b was also required to be an integer ....
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  5. #5
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    a.b-c=4

    b.c-a=3

    in equality, a, b, c are positive integers.

    What is total of a+b+c minumum?
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  6. #6
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    Quote Originally Posted by OPETH View Post
    a.b-c=4

    b.c-a=3

    in equality, a, b, c are positive integers.

    What is total of a+b+c minumum?
    Do not add a new question to an existing thread. Make a new thread.
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  7. #7
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    Sorry since we don't have the possible answers we just can quess what b might be
    b/(b-7)=a
    a can go to extreme and so b can go to extreme as well
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