<PRE><B>Question 126963</B>
A couple plan to have exactly three children. 
(a) Construct a tree diagram and list the sample space.
Yes, there are 8 possible patterns.
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(b) Find the probability that the family has at least two girls.
P(at least two girls) = P(2 girls) + P(3 girls) = (3/8)+(1/8) = 4/8 = 1/2
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Cheers,
Stan H.
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