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

Options

A. `1//2`
B. `1//4`
C. `1//3`
D. None of these

Answer

C

Explanation

Total cases are BB, BG GB, GG=4
Favourable cases are BB, BF, GB=3
Let P(A) = Probability of a boy in two children `=(3)/(4)`
The probability that the second the child is also a boy is `P(AnnB)=(1)/(4)`
We have to find `P(B//A)=(P(AuuB))/(P(A))=(1//4)/(3//4)=(1)/(3)`