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Question
If 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`
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Solution
If P(A) = `4/5`, and P(A ∩ B) = `7/10`, then P(B|A) is equal to `7/8`.
Explanation:
Given that: P(A) = `4/5`, and P(A ∩ B) = `7/10`
∴ P(B|A) = `("P"("A" ∩ "B"))/("P"("A"))`
= `(7/10)/(4/5)`
= `7/8`
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