Question

The following set of numbers respresents the average weekly scores of 9 preschoolers on a verbal aggression scale.

19.1, 18.9, 33.5, 18.7, 28.1, 31.5, 20.3, 30.1, 17.9

Consider this to be the entire population of scores. What is the standard deviation?

I already have the mean but I don't know how to figure out the rest.

Answer 1

Subtract each of the scores from the mean and square each difference. Find the sum of these squares. Divide that by the number of scores to get variance.

Standard deviation = square root of variance

I'll let you do the calculations.