For two events A and B, P(A) = 1/4, P(B) = 1/2 and P(A and B) = 1/8. What is P(A given B)?
Answer and explanation
Correct answer: C. 1/4
- Step 1: P(A given B) = P(A and B) / P(B). Step 2. = 1/8 / 1/2 = 1/4. Answer: 1/4. Why not the others: 1/2: That is P(B given A). 1/8: That is P(A) x P(B), which equals P(A and B) only for independent events. 5/8: That is P(A or B).
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