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Check whether the following probabilities P(A) and P(B) are consistently defined P(A) = 0.5, P(B) = 0.4, P(A ∪ B) = 0.8

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Question

Check whether the following probabilities P(A) and P(B) are consistently defined

P(A) = 0.5, P(B) = 0.4, P(A ∪ B) = 0.8

Sum
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Solution

Here P(A) = 0.5, P(B) = 0.4, P(A ∪ B) = 0.8

Now

P(A ∩ B) = P(A) + P(B) – P(A ∪ B)

= 0.5 + 0.4 – 0.8

∴ P(A ∩ B) = 0.1

Hence, P(A) and P(B) are consistently defined.

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Chapter 14: Probability - EXERCISE 14.2 [Page 307]

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NCERT Mathematics [English] Class 11
Chapter 14 Probability
EXERCISE 14.2 | Q 12. (ii) | Page 307

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