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    Just to be sure, is this the correct method of finding standard deviation from ungrouped data:



    Thanks.
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    (Original post by Abdul-Karim)
    Just to be sure, is this the correct method of finding standard deviation from ungrouped data:



    Thanks.
    I know nothing about spread sheets but by trying to read waht is going on I am assuming you are trying to find the standard deviation of 12 numbers

    I got a different answer...
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    (Original post by TeeEm)
    I know nothing about spread sheets but by trying to read waht is going on I am assuming you are trying to find the standard deviation of 12 numbers

    I got a different answer...
    Correct, could you point me in the right direction.

    From my understanding, I found the variance = (SumOf(frequency-mean)^2)/SumOfFrequency

    I don't know the keyboard codes for them ^ and then the standard deviation is simply the square root of that??

    Btw I've rounded the mean to the nearest integer, for simplification purposes.
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    (Original post by Abdul-Karim)
    Correct, could you point me in the right direction.

    From my understanding, I found the variance = (SumOf(frequency-mean)^2)/SumOfFrequency

    I don't know the keyboard codes for them ^ and then the standard deviation is simply the square root of that??

    Btw I've rounded the mean to the nearest integer, for simplification purposes.
    i only see 12 numbers ...

    what is the sum of frequency?
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    (Original post by TeeEm)
    i only see 12 numbers ...

    what is the sum of frequency?
    I would assume it's the sum of all the test scores, is it not?

    Or am I meant to divide by the sum of observations? which would be 12.
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    (Original post by Abdul-Karim)
    I would assume it's the sum of all the test scores, is it not?

    Or am I meant to divide by the sum of observations? which would be 12.
    I have no idea what the question is ...

    I am trying to decipher it by looking to the spreadsheet.

    If I am assuming the right things the variance is 2621/12
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    i checked using an online calculator ?

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    (Original post by the bear)
    i checked using an online calculator ?

    Yeah I got it, thanks.
 
 
 
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