StatisticsdrillSampling without replacement
A statistics problem from Statisticsdrill. Solve it with one answer box, with a fresh sample on every attempt and the worked steps and spreadsheet function in the answer, and it is checked the moment you submit.
The task
A shipment of 10 laptops contains 3 with a faulty battery. An inspector picks 5 laptops at random, without replacement. What is the probability that exactly 2 of them have a faulty battery? Round to 4 decimal places.
What this problem teaches
The formula: P(X = x) = C(D, x) × C(N - D, k - x) / C(N, k).
A hint if you get stuck
Count the ways: choose x of the faulty ones and k - x of the good ones, then divide by all ways to choose k.
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