Answer
P(k=2) = $\large\frac{3!}{2! \times 1!} \times 0.51^2 \times 0.49^1$ = $3 \times 0.2601 \times 0.49$ = 0.382
Answer
Answer
This is a problem of conditional probability
P(identical) = 0.3
=> P(both females and identical) = $0.3 \times 0.5$ = 0.15
=> P(both females and fraternal) = $0.7 \times 0.25$ = 0.175
Bayes' theorem
=> P(identical | both females) = $\large\frac{P(\text{both females and identical})}{P(\text{both females})}$ = $\large\frac{0.15}{0.15 + 0.175}$ = 0.4615