SOLUTION: If A and B are two events such that P(A) = 0.7 and P(B) = 0.5 and P((A u B)') = 0.1. Find P(A\B). [Note Here (A u B)' means complement of A union B]
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-> SOLUTION: If A and B are two events such that P(A) = 0.7 and P(B) = 0.5 and P((A u B)') = 0.1. Find P(A\B). [Note Here (A u B)' means complement of A union B]
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Question 1172393: If A and B are two events such that P(A) = 0.7 and P(B) = 0.5 and P((A u B)') = 0.1. Find P(A\B). [Note Here (A u B)' means complement of A union B] Answer by ikleyn(52775) (Show Source):
(1) From P(A U B)') = 0.1 we have P(A U B) = 1 - 0.1 = 0.9.
(2) From P(A U B) = P(A) + P(B) - P(A and B) we have
0.9 = 0.7 + 0.5 - P(A and B), which implies
P(A and B) = 0.7 + 0.5 - 0.9 = 0.3.
(3) Having P(A and B) just found, we obtain for the conditional probability
P( A | B ) = = = = 0.6. ANSWER
