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Let A and B be two events. If P(A | B) = P(A), then A is ______ of B.

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Question

Let A and B be two events. If P(A | B) = P(A), then A is ______ of B.

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Solution

Let A and B be two events. If P(A | B) = P(A), then A is independent of B.

Explanation:

∵ P(A|B) = `("P"("A" ∩ "B"))/("P"("B"))`

⇒ P(A) = `("P"("A" ∩ "B"))/("P"("B"))`

⇒ P(A ∩ B) = P(A).P(B)

So, A is independent of B.

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Chapter 13: Probability - Exercise [Page 286]

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NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 13 Probability
Exercise | Q 108 | Page 286

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