SOLUTION: This question is not from a text book. I am trying to find the standard deviation for this set of data. 75,65,50,90,80,60,70,85,80,85. The answer that i came up with is 42400 div

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Question 137525: This question is not from a text book.
I am trying to find the standard deviation for this set of data. 75,65,50,90,80,60,70,85,80,85. The answer that i came up with is 42400 divide by 10. is this the way how?
Thank you so much for your help.
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
The standard deviation for that set of numbers is 12.649....
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You need to find the mean of the numbers, which is 74
You need to find the differenece between 74 and each of the numbers in the set.
You need to square each of those differences.
You need to add up those squared values
You need to divide by (10-1) = 9 is you want the sample standard deviation
or by 10 if you want the population standard deviation.
You need to take the square root of the result.
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Cheers,
Stan H.