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Math Help - Competition results

  1. #1
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    Competition results

    Competition results:

    Result 10 20 30 40 50
    Participants 1 2 5 k 3


    Mean value of the results is 34. k=?

    Help?
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  2. #2
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    If the mean value of the results is 34, then you need to solve the following for k:

    \frac{1(10)+2(20)+5(30)+k(40)+3(50)}{1+2+5+k+3}=34
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  3. #3
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    The mean is equal to the sum of the results divided by the sum of the competitors, so:

    \frac{10+20+30+40+50}{1+2+5+k+3}=34

    From there, it's simple algebra. Solve for k.
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  4. #4
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    Quote Originally Posted by downthesun01 View Post
    The mean is equal to the sum of the results divided by the sum of the competitors, so:

    \frac{10+20+30+40+50}{1+2+5+k+3}=34

    From there, it's simple algebra. Solve for k.
    cpbrunner's got it right. You have to take the frquencies into account on the numerator. downthesun01 hasn't.
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  5. #5
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    My mistake. You're totally right
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