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Given P(A) = 0.4 and P(A ∪ B) = 0.7 Find P(B) if A and B are independent events

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प्रश्न

Given P(A) = 0.4 and P(A ∪ B) = 0.7 Find P(B) if A and B are independent events

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उत्तर

P(A) = 0.4

P(A ∪ B) = 0.7

Given A and B are independent

⇒ P(A ∩ B) = P(A) . P(B)

Now, P(A ∪ B) = P(A) + P(B) – P(A ∩ B)

(i.e.,) 0.7 = 0.4 + P(B) – (0.4)(P(B))

(i.e.,) 0.7 – 0.4 = P(B)(1 – 0.4)

0.3 = P(B) 0.6

⇒ P(B) = `0.3/0.6`

= `3/6`

= 0.5

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अध्याय 12: Introduction to probability theory - Exercise 12.3 [पृष्ठ २५९]

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सामाचीर कलवी Mathematics - Volume 1 and 2 [English] Class 11 TN Board
अध्याय 12 Introduction to probability theory
Exercise 12.3 | Q 10. (ii) | पृष्ठ २५९

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