Question 117072: find the standard deviation of
75 77 78 78 79 80 80 81 84 85 87 89 90 91
HELP
Answer by jim_thompson5910(35256)   (Show Source):
You can put this solution on YOUR website! First sort the numbers into ascending order (from least to greatest):
75,77,78,78,79,80,80,81,84,85,87,89,90,91
Now we need the mean. So add up all of the numbers and divide the sum by the number of numbers (which in this case is 14).
So the mean is 82.4285714285714
Now that we have the mean, we can use this formula to find the standard deviation:
Standard Deviation:^2}) where  is the arithmetic mean,  is the ith number, and  is the number of numbers
So we can replace N with 14
^2})
Replace with 82.4285714285714
^2})
Expand the summation (replace each  with the respective number)
Subtract the terms in the parenthesis
Square each term
Add up all of the terms
Multiply
Take the square root
So the standard deviation is
Here is an online standard deviation calculator that will check your work.
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