Question 826069
What are the odds of having 9 grandsons and no granddaughters?
P(9 of 10 boys) = 10C9(1/2)^10 = 10*(1/1024) = 10/1024
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P(not having 9 of 10 boys) = 1014/1024
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Odds for 9 of 10 boys = P(of)/P(not of) = 10:1014
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There's a 10th on the way. What are the odds of the 10th being a girl?
P(girl) = 1/2
P(not girl) 1/2
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odds of girl = P(of)/P(not girl) = 1:1
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Cheers,
Stan H.
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