Question 858063
In a society half of the families have one child ;the remaining families have  2 children per family?
What is the probability that a child is picked as a sibling?
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Let's say there are 10 families with 2 children:: total 20 children--all of
whom are "siblings".
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Then there are 10 families with 1 child:: total 10 children
P(child selected is a sibling) = 20/30 = 2/3
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Cheers,
Stan H.
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