Question

Use a calculator to find the Standard Deviation and the mean for the following set of data: 32, 61, 14, 23, 5, 25, 38

Answer 1

Yes, mean is \(approximately\) equal to 28.3.
To be exact, it is 28+2/7=28 2/7

If the numbers form a population, the mean is denoted \(\mu\).
If the numbers form a sample from a population, the mean is denoted xbar.

There are two formulas for standard deviation.
One is for a population, \(\sigma\)
The other is for a sample taken from a population, and so it is an approximation, s.
\(\sigma=\sqrt{\sum(x-\mu)^2/N}\) where N is the size of the population
\(s=\sqrt{\sum(x-xbar)^2/(n-1)}\) where n is the size of the sample.

If you still have doubts, read the following:
http://davidmlane.com/hyperstat/A16252.html