Question

if you know for certain that a friend of yours has two children and that at least one of them is a boy, what is the probability that the other is also a boy?

Answer 1

Hi<3

Explanation:

The probability that the other child is also a boy, given that you know for certain that at least one of your friend's children is a boy, is 1/3 or approximately 33.3%1

To understand why, we can consider the four possible combinations of genders for the two children: boy-boy (BB), boy-girl (BG), girl-boy (GB), and girl-girl (GG).

Since you know for certain that at least one child is a boy, we can eliminate the GG option. This leaves us with three remaining equally likely possibilities: BB, BG, and GB. Out of these three possibilities, only one of them involves both children being boys (BB), while the other two involve a boy and a girl (BG and GB).

Therefore, the probability that the other child is also a boy is 1 out of 3, or 1/3.