The boy born on a Tuesday
A parent has two children. You learn that at least one is a boy born on a Tuesday. Assuming boys and girls are equally likely and birth-days are uniform and independent, what is the probability that both children are boys? Give your answer as a decimal (to 2 decimals).
Show hints (2)+
- Label each child by (sex, day): 14 equally likely tags, 196 ordered pairs.
- Count ordered pairs with at least one boy-Tuesday using inclusion-exclusion.
Answer
Reveal answer →Final answer
0.48 (± 0.01)
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