1. Let X1and X2be two iid random variables. They each have a variance which we will call V(X).V(X) = 10.What does V(X1+ X2+ X2) equal?Remember, you have to explain how you got your answer.This is true for other questions, as well.
2. There are two random variables, X and Y.Let p(X = + 2) = 0.7, p(X = + 4) = 0.2, p(X = + 8) = 0.1.Furthermore, let p(Y = - 8) = 0.2, p(Y = - 3) = 0.3, p(Y = + 1) = 0.5.Finally, let E(XY) = - 3.8.What does Cov(X,Y) equal?