A man visits a couple who have two children.One of them, a boy, comes in to the room. Find the probability p that other is also a boy
a) 1/3 b) 2/3 c) 1/2 d) 3/4
Correct Ans: a) 1/3
However I am getting answer as 1/2.My solution is as follows.
The couple has two children, hence the sample space is as follows.
B- Boy G - Girl
BB BG GG ( BG and GB mean the same thing as Girl,Boy), but it is already known that one is boy.So the sample space reduces to
BB BG
So now p is 1/2
Is there some mistake is my approach ?