SOLUTION: Out of 2400 families with 3 children each about.how many of these families would have at least one boy?

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Question 1089108: Out of 2400 families with 3 children each about.how many of these families would have at least one boy?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
If the probability of a baby being a boy,
and the probability of a baby being a girl
are both 1%2F2 ,
Then the probability of a family with 3 children having 3 girls would be
%281%2F2%29%2A%281%2F2%29%2A%281%2F2%29=1%2F8 .
As a consequence the probability of of a family with 3 children having at least one boy is
1-1%2F8=7%2F8=0.875 .
The number 2400 is a pretty large number,
so we can be confident that about 7%2F8 of those families will have at least one boy.
That is 2400%2A%287%2F8%29=300%2A7=2100 .
About highlight%282100%29 of those 2400 families would have at least one boy.