<PRE><B>Question 694611</B>
In a box of 23 parts, 7 are defective. Two parts are selected at random without replacement. What is the probability that at least one part is defective?
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P(at least one defective) = 1 - P(none defective)
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To find P(none defective):
# of ways to succeed: 16C2
# of possible pairs:: 23C2
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Ans: 1 - [16C2/23C2] = 1 - 0.4743 = 0.5257
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Cheers,
Stan H.
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