Two events, A and B, have marginal probabilities P (A) = 0:2 and P (B) = 0:5, respectively. Their joint probability is P (A∩B) = 0:4.
a. Are they statistically independent? Why or why not?
b. What is the probability of A or B or both occurring?
c. In general, what must be true for two events be both statistically independent and mutually exclusive?