Answer: [tex]\bold{\dfrac{7}{8}=87.5\%}[/tex]
Step-by-step explanation:
"At least one girl" means P(1 girl) + P(2 girls) + P(3 girls) or 1 - P(all boys)
I will use the latter: 1 - P(all boys)
P(all boys) = [tex]\dfrac{1}{2}\times \dfrac{1}{2}\times \dfrac{1}{2}=\dfrac{1}{8}[/tex]
[tex]1 - P(all\ boys) \quad = \quad 1-\dfrac{1}{8}\quad =\large\boxed{\dfrac{7}{8}}[/tex]
