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Question
Let A and B be two events. If P(A) = 0.2, P(B) = 0.4, P(A ∪ B) = 0.6, then P(A|B) is equal to ______.
Options
0.8
0.5
0.3
0
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Solution
Let A and B be two events. If P(A) = 0.2, P(B) = 0.4, P(A ∪ B) = 0.6, then P(A|B) is equal to 0.
Explanation:
From the given data P(A) + P(B) = P(A ∪ B).
This shows that P(A ∩ B) = 0.
Thus P(A|B) = `("P"("A" ∩ "B"))/("P"("B"))` = 0.
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