JEE Mains · Maths · STD 11 - 14. probability
Assume that each born child is equally likely to be a boy or a girl. If two families have two children each, then the conditional probability that all children are girls given that at least two are girls is
- A \(\frac{1}{10}\)
- B \(\frac{1}{17}\)
- C \(\frac{1}{12}\)
- D \(\frac{1}{11}\)
Answer & Solution
Correct Answer
(D) \(\frac{1}{11}\)
Step-by-step Solution
Detailed explanation
\(P(B o y)=P(g i r l)=\frac{1}{2}\) Required probability \(=\frac{\text { all four girls }}{\text { Atleast two girls }}\)…
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