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squash (榜样WSN) 于 (Thu Apr 12 12:44:31 2007) 提到:
a deck of cards, (52 cards), n people, each one gets two cards.
What's the odd that two people both have pair of Aces?
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litaihei (李太黑) 于 (Thu Apr 12 14:50:40 2007) 提到:
C(n-4,52-4)/C(n,52) * C(2,n) * (2n-4)!/2^(n-2) * 2^(n)/(2n)!
first part comes from we must have 4 Aces.
second part comes form pick up two people with pari of Aces.
third part comes form the tota |
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