HardProbability
The Tuesday Boy
Jane StreetSIG / Susquehanna
A family has two children. You learn that at least one of them is a boy born on a Tuesday (assume boys and girls, and all birth days, are equally likely and independent). What is the probability that both children are boys?
Approach
Enumerate (sex, birth-day) pairs for both children.
Watch the double-count of two Tuesday boys.
Answer
Show the final answer
The answer is 13/27. Sign in free for the full worked solution and to check your own answer.
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