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If A and B are two events such that P(A) = 0.7, P(B) = 0.4 and P(A B) = 0.5, where B denotes the complement of B, then P (B (A B) ) is equal to
(3) 14
P (B (A B) ) = P (B (A B) )P(A B)
B (A B) = (B A) (B B) = A B
P(A B) = P(A) - P(A B) = 0.7 - 0.5 = 0.2
P(A B) = P(A) + P( B) - P(A B) = 0.7 + 0.6 - 0.5 = 0.8
P (B (A B) ) = 0.20.8 = 14
Answer: (3)
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