@ Probability

A couple has two children. One of them is a boy. What is the probability that the other one is also a boy?

I think answer should be 1/2.
As total no of set will be (B,B) and (B,G).
so, probability of one boy will be 1/2.

1/2 is not correct

can you explain why it won't be 1/2.
There is only two set (B,B) and (B,G). (G,B) will be same as (B,G) and (G,G) won't come into the picture because one of them is boy.
So, probability will be 1/2.
If not then give me ur reasoning.

Even I feel answer should be 1/2.

Well the correct answer is 1/3. Can somebody try to figure out y it is so?

Lucifer, Amit,
If I understand the problem correctly, number of kids is fixed to 2 and just "one of them" is a boy.
In that case, we have three possibilities for the kids (say A and B)

A | B
Boy | Girl
Boy | Boy
Girl | Boy

So, isnt it obvious that odds of both being boys is 1/3

why you are taking B,G and G,B both. I think both are same in this case.

There is difference.
Question says "One of them is boy"
So "A" can be boy or "B" can be boy. ( B,G and G,B are different cases)
or Both of them. That's why answer is 1/3

i think this question is a paradox so ur answer can not be justifiable.
Please go through the below link in wiki..

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