Engineering Board Exam Reviewer · Conditional Probability and Bayes' Theorem · hard
A family has two children. Given that at least one of them is a boy, what is the probability that both are boys?
- 1/2
- 1/4
- 1/3
- 2/3
Answer
C. 1/3
Solution
The equally likely outcomes are BB, BG, GB, GG. With at least one boy, three remain: BB, BG, GB. Only BB has two boys, so P= 13.
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