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Question
If A and B are events such as that P(A) = `1/2`, P(B) = `1/3` and P(A ∩ B) = `1/4`, then find
1) P(A / B)
2) P(B / A)
Solution
P(A) = 1/2 P(B) = 1/3 P(A∩B) = 1/4
`P(A "/" B) = (P(A∩B))/P(B) = (1/4)/(1/3) = 3/4`
`P(B "/" A) = (P(A ∩ B))/(P(A)) = (1/4)/(1/2) = 1/2`
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