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Math Help - Question in calculating the median, upper and lower quartiles

  1. #1
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    Question in calculating the median, upper and lower quartiles

    I have the data
    1.63
    1.79
    1.79
    2.36
    2.54
    2.60
    3.01
    3.25

    I calculated the median to be 2.45, then to calculate the lower quartile (1.79+1.79)/2 = 1.79. But something is wrong with the upper quartile. I thought I would have to do (2.60+3.01)/2 = 2.805. But if I use excel to calculate the upper quartile I get 2.7025? What did I do wrong? Thanks.
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  2. #2
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    Your hand calcs are correct, what formula did you use in excel?
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  3. #3
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    Quote Originally Posted by pickslides View Post
    Your hand calcs are correct, what formula did you use in excel?
    I used =QUARTILE((range of data),3)
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  4. #4
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    try =percentile("range of data",0.75)

    Does it give a different answer?
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  5. #5
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    Quote Originally Posted by pickslides View Post
    try =percentile("range of data",0.75)

    Does it give a different answer?
    No I get the same thing as =quartile("range of data",3)
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  6. #6
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    I see, I have the same problem.

    Must be something quirky with how excel calculates this parameter.
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