<PRE><B>Question 265805</B>
Eight students are chosen at random from a group of twenty of which Alex, Beth and Fraser are a part. What is the probability that Alex, Beth and Fraser are all among the chosen? 
I have tried the following: 
8C3/18C10 = 0.00128 
which seems WAY too small a probability. 
Any thoughts?
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P(A,B,C are in the group chosen) = 1 - P(they are not among the chosen)
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P(they are not among the chosen) = 17C8/20C8 = 24310/125970 = 0.1930..
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So P(A,B,C are in the group chosen = 1-0.1930 = 0.8070
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Cheers,
Stan H.</PRE>