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Math Help - Question about geometric series

  1. #1
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    Question about geometric series

    I don't quite understand half-life. How to solve this question?
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    Quote Originally Posted by yida View Post
    I don't quite understand half-life. How to solve this question?
    y = y_0\left(\frac{1}{2}\right)^{\frac{t}{h}}

    y = amount left at any time t in hrs

    y_0 = amount at t = 0

    h = half-life in hrs
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  3. #3
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    the answer is wrong
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  4. #4
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    Quote Originally Posted by yida View Post
    the answer is wrong
    what answer are you speaking of ?

    I gave you the general function for half-life, not an "answer".
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    I use y0=55
    t=12 h=7.2
    but I got wrong answer
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  6. #6
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    what "wrong answer" did you get?
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  7. #7
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    55(0.5)^(12/7.2)
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  8. #8
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    Quote Originally Posted by yida View Post
    55(0.5)^(12/7.2) = 17.324 mg
    ... and that is not wrong.
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