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Lecture 5
The birthday problem
Gamblers ruin
Polya's urn
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Problem # 3: The birthday
problem
3 K1 2
X X X X1 2 3 K
X1, X2, . . . , XK are chosen at random from the numbers 1, 2, . . . , N
· What is the probability that at least 2 of the K cards have
the same (random) number on them?
