Conditional probability · Family · difficulty 4 of 5
A boy born on a Tuesday
A family has two children. Each child, independently, is a boy or a girl with probability 1/2 each, and each child is equally likely to have been born on any of the 7 days of the week, independently of everything else. You ask a parent: “Is at least one of your children a boy born on a Tuesday?” The parent answers truthfully: yes. What is the probability that both children are boys?
Answer with a probability. First lock in a gut guess with an 80% range, then solve it properly, then watch a simulation settle on the truth.
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