<PRE><B>Question 255892</B>
To control the quality of their product, the bright-light company inspects three light bulbs out of each batch of ten bulbs manufactured. 
If a defective bulb is found, the batch is discarded. Suppose a batch contains two defective bulbs. What is the probability that the batch will be discarded?
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P(no defective bulb in set of 3 from 10) = 8C3/10C3 = 56/120
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P(you find a defective bulb when you select 3 from 10)
= 1 - p(you find no defective) 
= 1- (56/120) 
= 64/120 
= 8/15
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Cheers,
Stan H. </PRE>