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Evaluate P(A ∪ B), if 2P(A) = P(B) = 513 and P(A | B) = 25

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प्रश्न

Evaluate P(A ∪ B), if 2P(A) = P(B) = `5/13` and P(A | B) = `2/5`

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उत्तर

It is given that,

2P(A) = P(B) = `5/13`

`\implies` P(A) = `5/26` and P(B) = `5/13`

`\implies` P(A | B) = `2/5`

`\implies (P(A ∩ B))/(P(B)) = 2/5`

`\implies P(A ∩ B) = 2/5 xx P(B)`

= `2/5 xx 5/13`

= `2/13`

It is known that,

P(A ∪ B) = P(A) + P(B) – P(A ∩ B)

`\implies`  P(A ∪ B) = `5/26 + 5/13 - 2/13`

`\implies` P(A ∪ B) = `(5 + 10 - 4)/26`

`\implies` P(A ∪ B) = `11/26`

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अध्याय 13: Probability - Exercise 13.1 [पृष्ठ ५३८]

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एनसीईआरटी Mathematics Part 1 and 2 [English] Class 12
अध्याय 13 Probability
Exercise 13.1 | Q 4 | पृष्ठ ५३८

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