Same chapter3 marksDifficulty: Medium
If P(A) = 1/3 and P(B) = 1/2 and A and B are independent, find P(A ∩ B) and P(A ∪ B).
Probability
3 marksDifficulty: Medium
Define conditional probability and state the multiplication theorem.
Original Khojo Papers practice question — not from a past board paper.
Answer
The conditional probability of A given B, written P(A|B), is the probability that A occurs given that B has occurred, and it equals P(A ∩ B)/P(B) provided P(B) is not zero. The multiplication theorem follows: P(A ∩ B) = P(B) P(A|B) = P(A) P(B|A).
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
A and B are independent exactly when P(A|B) = P(A).
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