Mean: a set of numbers arranged in sequence, in the middle. That is, the number of n is arranged as (N+ 1)/2. If n is an even number, it is the average of the middle two numbers.
.
Variance = Sigma (Xi mean) 2/n
Standard deviation 2 = variance
"One" 20 17 Postgraduate Entrance Examination for Mathematics-An Outline of Probability Theory and Mathematical Statistics. Do yo