Qm
Probability

First defective on the second draw

negative-hypergeometricwaiting-timewithout-replacement

A tray holds 4 defective parts and 6 good parts, 10 in total. You test parts one at a time, without replacement.

What is the probability that the first defective part appears on exactly the second draw?

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The theory behind this question.

The Exponential DistributionThe Geometric DistributionThe Negative Binomial DistributionThe M/M/1 Queue and Waiting-Time DistributionsThe ABRACADABRA Problem

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