Question 197998
Three defective electric toothbrushes were accidently shipped along with 17 non-defective. 
a. what is the probability that the first two selected will be defective.
Ans: 3C2/17C2 = 3/136
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b. what is the probability the first two sold will not be defected
Ans: 14C2/17C2 = 0.669...
Cheers,
Stan H.