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Question
If A and B are two events associated with a random experiment such that
P(A) = 0.5, P(B) = 0.3 and P (A ∩ B) = 0.2, find P (A ∪ B).
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Solution
Given:
P(A) = 0.5, P (B) = 0.3 and P (A ∩ B) = 0.2
By addition theorem, we have:
P (A ∪ B) = P(A) + P (B) - P (A ∩ B)
⇒ P (A ∪ B) = 0.5 + 0.3 - 0.2
= 0.8 - 0.2 = 0.6
Hence, P (A ∪ B) = 0.6
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