Answer:
0.875 or 87.5%
Step-by-step explanation:
For each child, there is an equal 1 in 2 probability of having a girl or a boy.
The probability of having at least one girl out of three children includes the probability of having 1, 2 or 3 girls. It can also be written as 100% minus the probability of having all boys, therefore:
[tex]P(G\geq 1)=1-P(B=3)\\P(G\geq 1)=1-(\frac{1}{2}*\frac{1}{2}*\frac{1}{2})\\ P(G\geq 1)=0.875[/tex]
The probability of having at least one girl is 0.875 or 87.5%.