Question

If A and B are two mutually exclusive events of a random experiment and P(not A) = 0.45, P(A ∪ B) = 0.65, then find P(B).

Answer 1

P(not A) = 0.45

1 – P(A) = 0.45

P(A) = 1 – 0.45 = 0.55

P(A ∪ B) = P(A) + P(B)

0.65 = 0.55 + P(B)

0.65 – 0.55 = P(B)

0.10 = P(B)

P(B) = 0.1