Question

If M and N are any two events, the probability that at least one of them occurs is ______. 

Options

• P(M) + P(N) – 2P(M ∩ N)

• P(M) + P(N) – P(M ∩ N)

• P(M) + P(N) + P(M ∩ N)

• P(M) + P(N) + 2P(M ∩ N)

Answer 1

If M and N are any two events, the probability that at least one of them occurs is P(M) + P(N) – P(M ∩ N). 

Explanation:

If M and N are any two events, then

P(M ∪ N) = P(M) + P(N) – P(M ∩ N)