You are given N addressed letters and N addressed envelopes. If you randomly put one letter in each envelope, what is the probability that no letter ends up in the correct envelope?
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Waiting for An Ace
How many cards do you need to deal from a standard deck, on average, to get your first ace? A standard deck contains 52 cards, four of which are aces.
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The Hotel Problem
You are driving down a one-way road and pass a strip of a large number, N, of hotels. These all have different rates, arranged randomly. You want to maximize your chance of choosing the cheapest hotel, but you can’t return to one you’ve passed up. Assume that your only goal...
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Flipping a Coin
From the book The Green-Eyed Dragons and Other Mathematical Monsters
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Coin Puzzles
A pile of coins of the same size, round.
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