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Question
If for any two events A and B, P(A) = `4/5` and P(A ∩ B) = `7/10`, then `P(B/A)` is equal to ______.
Options
`1/10`
`1/8`
`7/8`
`17/20`
Solution
If for any two events A and B, P(A) = `4/5` and P(A ∩ B) = `7/10`, then `P(B/A)` is equal to `underlinebb(7/8)`.
Explanation:
P(A) = `4/5`, P(A ∩ B) = `7/10`
So `P(B/A) = (P(B ∩ A))/(P(A))`
= `(7/10)/(4/5)`
= `7/8`.
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