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A couple has two children, Find the probability that both children are females, if it is known that the elder child is a female. - Mathematics

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प्रश्न

A couple has two children, Find the probability that both children are females, if it is known that the elder child is a female.

योग

उत्तर

Let A = both children are girls = [GG]

B = The elder child is a girl = {GG, GB}

P(A ∩ B) = `1/4` and P(B) = `1/2 = 2/4`

∴ `P(A/B) = (P(A ∩ B))/(P(B))`

= `1/4 ÷ 2/4`

= `1/2`

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अध्याय 13: Probability - Exercise 13.6 [पृष्ठ ५८२]

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एनसीईआरटी Mathematics [English] Class 12
अध्याय 13 Probability
Exercise 13.6 | Q 2.2 | पृष्ठ ५८२

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