Question

Given P(A) = `3/5` and P(B) = `1/5`. Find P(A or B), if A and B are mutually exclusive events.

Answer 1

A and B are mutually exclusive events, then

P(A ∩ B) = 0

P(A) = `3/5`, P(B) = `1/5`

P(A or B) = P(A ∪ B) = P(A) + P(B) – P(A ∩ B)

∴ P(A ∪ B) = `3/5 + 1/5 - 0`

= `4/5`