English

If P(A) = 45, and P(A ∩ B) = 710, then P(B|A) is equal to ______.

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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`

MCQ
Fill in the Blanks
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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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Chapter 13: Probability - Exercise [Page 279]

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NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 13 Probability
Exercise | Q 56 | Page 279

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