<PRE><B>Question 983635</B>
A shipment of 250 netbooks contains 3 defective units. 
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Binomial Problems with p(defective) = 3/250 ; p(good) = 247/250
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Determine how many ways, and the probability, a vending company can buy three of these units and receive
(a) no defective units.
# of ways:: 247C3 = 2481115 ways
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P(no defect) = 247C3/250C3 = 0.9643
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(b) all defective units.
# of ways:: 3C3 = 1
P(3 defective) = 1/250C3
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(c) at least one good unit.
# of total ways - # of ways with no defects = 250C3-247C3 = 91885
P(at least one defect) = 91885/250C3 = 0.0357
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Cheers,
Stan H.
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