An urn has n balls and we take balls from it with replacement until each ball has been drawn at least one. X denotes the number of draws required. What is the expected value and variance of X? I think X is at least n, is it true? And how should I find the expected value of it?
2026-03-27 00:03:43.1774569823
Expected value of random variable which is the number of drawns required
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