<PRE><B>Question 319507</B>
A population consists of 15 items, 10 of which are acceptable. In a sample of 4 items, what is the probability that exactly 3 are acceptable? Assume the samples are drawn without replacement
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# of ways to get 3 acceptable: 4C3 = 4
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# of ways to get 3 randomly: 10C3 = (10*9*8)/(1*2*3) = 120
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P(3 acceptable) = 4/120 = 1/30
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Cheers,
Stan H.
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