Boy or Girl Paradox
Explore the tricky conditional probabilities of sibling gender combinations
A family has two children. You are given some information about them. What is the probability that both are boys?
Probability (Both Boys)
1/3
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Why 1/3? If you only know "at least one is a boy," the possible families are {BB, BG, GB}. Only one of these three cases has two boys. If you know "the older is a boy," the options are restricted to {BB, BG}, making it 1/2.
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