Q#15

Let X be a random variable with the following probability distribution. Value x of X P(X=x) 40 0.15 50 0.25 60 0.30 70 0.15 80 0.10 90 0.05 Complete the following. (If necessary, consult a list of formulas.) (a) Find the expectation E (X) of X. E (X) = 1 (b) Find the variance Var(X) of X. Var (x) = 0