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MHT CET2008MathematicsProbability

A parents has two children. If one of them is boy, then the probability that other is, also a boy, is

Options

  1. A1 / 2
  2. B1 / 4
  3. C1 / 3
  4. DNone of these

Correct answer

C. 1 / 3

Step-by-step solution

Total cases are B B, B G, G B, G G=4 Favourable cases are B B, B G, G B=3 Let P(A)= Probability of a boy in two children = 3 4 The probability that the second child is also a boy is P(A B)= 1 4 We have to find P(B / A)= P(A B) P(A) = 1 / 4 3 / 4 = 1 3

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