# Question: a we define the standard deviation to be the average...

###### Question details

a) We define the standard deviation to be the average of all deviations from the mean. To express this definition mathematically, explain why we need to take the square of deviations, divide by n-1, and then take the square root.

b) Use the formula above to find the standard deviation s of the following sample X= {2, 3, 2, 6, 7 }.

c) Use the built-in statistics function “1-Var Stats” in your TI-83/84 calculator to verify your answer above (show the “complete” output).