Two children
A family has two children. Given that at least one of them is a boy, what is the probability that both are boys? (As a twist, consider how the answer changes if instead you're told the older child is a boy.)
Show hints (2)+
- Enumerate the four equally likely birth orders.
- Condition by removing the outcomes ruled out.
Answer
Reveal answer →Final answer
0.3333 (± 0.01)
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Asked at: Jane Street, SIG