A family has two kids, and at least one is a boy. Find the probability that both children are boys.

Question: A family has two kids, and at least one is a boy. Find the probability that both children are boys.Solution:Let B represent a boy and G a girl.For 2 children, the total possible combinations are 4:GG (both girls)GB (girl then boy)BG (boy then girl)BB (both boys)If at least one child is a boy, we exclude GG.So, the valid outcomes are: GB, BG, BB — a total of 3 outcomes.Out of these, only BB has both children as boys.So, the probability that both kids are boys given that at least one is a boy = 1/3.