Question

Valerie has 9 different pairs of shoes in her closet. She randomly chooses a shoe (without replacement) until she has a pair of matching shoes. Let X = number of shoes selected until a pair is found. Find the probability mass function, the expected value, and the standard deviation of X. HINT: IT IS NOT BINOMIAL NOR GEOMETRIC, PROBABILITY IS NOT CONSTANT. MUST BE SOLVED WITHOUT USING PROBABILITY DISTRIBUTIONS

Answer 1

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