Chapter 7, Survey Sampling

Solution 39

The probability of choosing atleast one defected item in the sample, = 1 - Probability of choosing no defected item in the sample.

We have total items and of them are defected. Thus the probability of choosing a sample of size with no defected item = .

Thus . Now we can plot this function with and as variables to get the desired sample size. Skipping the sketch part :)

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