<PRE><B>Question 149493</B>
In a shop there are 20 customers, 18 of whom will make a purchase.
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P(a random person in the group makes a purchase) = 18/20 = 9/10
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If three customers are selected, one at a time, at random, what is the probability that all will make a purchase?
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This is a binomial problem with p=0.9 
P(3 of 3 make a purchase) = 0.9^3 = 0.729
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Cheers,
Stan H.





 Is it 0.7717, 0.7605, 0.8524, or 0.8808. 
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