A group of four components is known to contain two defectives. An inspector tests the components one at a time until the two defectives are located. Once she locates the two defectives, she stops testing. Let Y denote the number of the test on which the second defective is found. Find the probability distribution for Y assuming that testing is carried out until 2 are proven to be defective.
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Since there are two defectives in the group of four components, the second defective can be found on the second test (if the first two components tested are both defective), the third test (if one of the first two components is defective and the other is not), or Show more…
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