If two events are mutually exclusive, P(A or B) equals?

If two events are mutually exclusive, P(A or B) equals?

• A. P(A) * P(B)
• B. P(A) - P(B)
• C. P(A) / P(B)
• D. P(A) + P(B)

Answer: (D)

Two events that are mutually exclusive cannot happen at the same time, so their intersection has probability zero. When you ask for A or B, you’re looking at the union of two disjoint outcomes. For disjoint (mutually exclusive) events, the probability of A ∪ B is simply the sum of their probabilities: P(A ∪ B) = P(A) + P(B). The other expressions don’t fit because multiplication corresponds to a relationship like independence, and subtraction or division don’t correctly account for the lack of overlap in mutually exclusive events.

Two events that are mutually exclusive cannot happen at the same time, so their intersection has probability zero. When you ask for A or B, you’re looking at the union of two disjoint outcomes. For disjoint (mutually exclusive) events, the probability of A ∪ B is simply the sum of their probabilities: P(A ∪ B) = P(A) + P(B). The other expressions don’t fit because multiplication corresponds to a relationship like independence, and subtraction or division don’t correctly account for the lack of overlap in mutually exclusive events.