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Question
If P(A) = 0.8, P(B) = 0.5 and P(B|A) = 0.4, find P(A ∪ B)
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Solution
It is given that P(A) = 0.8, P(B) = 0.5, and P(B|A) = 0.4
P(A∪B) = P(A) + P(B) − P(A∩B)
⇒P(A∪B)=0.8 + 0.5 − 0.32 = 0.98
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