Hi, Given sample size as 25 and mean as 56, can any one of you help me calculating standard deviation?
You need to have information about the sample. If you have the sample just add up the sums of squares (i.e. (x_i - mean)^2) for every i from 1 to 25 and divide that total answer by n - 1 (n = 25) in your case.
The standard deviation of returns is important to investors because it is the standard measure of investment risk, and investment risk is the degree of uncertainty of earning the expected rate of return. As you will see, the standard deviation of returns can be used to estimate the probability of the return on an investment falling within a given range relative to the expected rate of return in any given period.
maths tutor | statistics tutor