369.The Last Cherry
★★★classical probabilityCh. 1 — Classical Probability and Combinatorics444+ Problems in Probability
Amy has a bowl of 5 red cherries and 8 purple cherries. She takes out cherries one at a time, uniformly at random, until there are no red cherries left. What is the probability that the bowl is then empty?
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The bowl ends empty exactly when a particular cherry is drawn last. Which one?
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