Answer:
The probability that the family has at least one girl, given that they have at least one boy 0.80.
Step-by-step explanation:
Construct the sample space for all the 5 children as follows:
S = {GGGGG, GGGGB, GGGBB, GGBBB, GBBBB and BBBBB}
There are a total of 6 outcomes.
First compute the probability of at least 1 boy.
Favorable outcomes : {GGGGB, GGGBB, GGBBB, GBBBB and BBBBB} = 5
Then the probability of at least 1 boy is,
[tex]P(At\ least\ 1\ boy)=\frac{5}{6}[/tex]
Of these 5 samples the sample space for at least 1 girl is:
{GGGGB, GGGBB, GGBBB and GBBBB} = 4
Then the probability of at least 1 girl given at least 1 boy is,
[tex]P(At\ least\ 1\ girl|At\ least\ 1\ boy)=\frac{4}{5}=0.80[/tex]
Thus, the probability of at least 1 girl given at least 1 boy is, 0.80.