Let x be a random variable with the following probability distribution. Value x of X P ( X=x) 10 0.15 20 0.20 30 0.20 40 0.30 50 0.05 60 0.10 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