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Question
A and B are two events such that P (A) ≠ 0. Find P (B|A), if A is a subset of B.
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Solution
P (B|A) = `(P (A cap B))/(P (A))`
`= (P (A))/(P(A)) = 1` ...(∵ A ⊂ B ⇒ A ∩ B = A)
A is a subset of set B.
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