Tossing coins

207 viewsCombinatorics Probability

A guy is tossing coins. He has one coin at the beginning.Anytime he tosses a coin, if it’s right-side up, he can take the coin back and get a new one, otherwise the coin he tossed will be taken away. He won’t stop tossing the coin until all of his coins are taken away. What is the expected value of the times he tosses coins?

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