Using the probabilities found in Exercise 11, where A = {1, 2}, B = {1, 3}, Pr(A)

Question:

Using the probabilities found in Exercise 11, where A = {1, 2}, B = {1, 3}, Pr(A) = 0.4, Pr(B) = 0.6.
The formula for the probability of the union of two events,
Pr(A ⋃ B) = Pr(A) + Pr(B) - Pr(A ⋂ B),
(from Section 6.3, Exercises 13-16) is simpler when events are independent.
Pr(A ⋃ B) = Pr(A) + Pr(B) - Pr(A)Pr(B).
Test the formula on the following independent events.