SOLUTION: A family has 4 children. Assume that each child is as likely to be a boy as it is to be a girl. Find the probability that the family has 4 girls if it is known the family has at le

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Question 1165953: A family has 4 children. Assume that each child is as likely to be a boy as it is to be a girl. Find the probability that the family has 4 girls if it is known the family has at least one girl.
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
the sample space for number of girls in 4 children
1----4----6----4----1 from Pascal's triangle
denominator is 16 and the probability of 0 girls is 1/16, all the way over to 4 girls, where the probability is 1/16.
So if they have at least one girl, there are 15 possibilities for the other numbers
4 are just 1
6 are 2
4 are 3
1 is 4
so the answer is 1/15.