For a sample of n participants the relative frequencies are

Question

For a sample of n participants, the relative frequencies are f0/n = .2, f₁/n = .4, f₂/n = .2, f3/n = .15, and f4/n = .05. The sample mean is 1.45. Using your answer to given Exercise, verify that the sample variance is 1.25

Exercise

Devise a method for computing the sample variance based on the frequencies, fx.