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Math Help - complicated problem , who's gonna be the brainy here ?

  1. #1
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    complicated problem , who's gonna be the brainy here ?

    hi guyz

    i need the solution to that problem ASAP plz

    10% more than 10% less than x is what percent of 10 x?


    any ideas !
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  2. #2
    Senior Member mollymcf2009's Avatar
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    Quote Originally Posted by sehs View Post
    hi guyz

    i need the solution to that problem ASAP plz

    10% more than 10% less than x is what percent of 10 x?


    any ideas !
    10%

    10% more than 10% less than x is just x. So x is 10% of 10x.
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  3. #3
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    Quote Originally Posted by sehs View Post
    10% more than 10% less than x is what percent of 10 x?
    translation:

    1.1(0.9(x)) = k(10x)

    .99x = 10kx

    .99 = 10k

    .099 = k

    9.9% = k


    10% more and 10% less is not the same as 10% more than 10% less.
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  4. #4
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    e^(i*pi)'s Avatar
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    Quote Originally Posted by sehs View Post
    hi guyz

    i need the solution to that problem ASAP plz

    10% more than 10% less than x is what percent of 10 x?


    any ideas !
    If we start with 10x then 10% less ie 90% of the original value we get

    10x(1-0.1) = 9x

    We then put 10% back on, but now it will be 10% of the 9x so we won't get 10x but rather:

    9x(1+0.1) = 9.9x.

    In one step it would be

    10x(1-0.1)(1+0.1) which is the difference of two squares and simplifies to 10(1-0.01) = 9.9
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  5. #5
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    thx much guyz
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