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प्रश्न
If A and B are two events associated with a random experiment such that
P (A ∪ B) = 0.8, P (A ∩ B) = 0.3 and P \[(\bar{A} )\]= 0.5, find P(B).
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उत्तर
Given:
P (A ∪ B) = 0.8, P (A ∩ B) = 0.3 and
By addition theorem, we have:
P (A ∪ B) = P(A) + P (B) - P (A ∩ B)
⇒ 0.8 = 0.5 + P (B) - 0.3
⇒ 0.8 = 0.2 + P (B)
⇒ P (B) = 0.8
0.2
= 0.6
Hence, P (B) = 0.6
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