SOLUTION: Assume that the probability of a boy being born is the same as the probability of a girl being born. Find the probability that a family with four children will have the given compo

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Question 1098414: Assume that the probability of a boy being born is the same as the probability of a girl being born. Find the probability that a family with four children will have the given composition: Three boys and one girl.
I think I know what the answer is, but I don't know how to get to the answer properly. Can you please show me how to work through this problem? Thank you.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Look at the possible outcomes, there are 2%5E4 or 16 of them.
I will also count the number of boys in each outcome.
GGGG=0
GGGB=1
GGBG=1
GGBB=2
GBGG=1
GBGB=2
GBBG=2
GBBB=3
BGGG=1
BGGB=2
BGBG=2
BGBB=3
BBGG=2
BBGB=3
BBBG=3
BBBB=4
So out of the 16 outcomes, count the number with the given number of boys,
B=0,1
B=1,4
B=2,6
B=3,4
B=4,1
So the probability of having three boys and one girl are,
P%28B=3%29=4%2F16=1%2F4