Answer:
0.1024
Step-by-step explanation:
Given that in a country there is only one of every 5 births is a girl.
i.e probability of a child born being a girl = 0.20
EAch birth is independent of the other and there are only two outcomes
Hence X no of girls will be binomial.
Required probability
= Probability that the first girl they have is the fourth baby
= Probability for first three children to be boys and fourth be a girl
Since each birth is independent of other, we have
Required probability
=[tex]0.8^3*0.2\\=0.1024[/tex]
