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请教高中数学题

ruby88 2009-03-15 10:25:32 ( reads)

Five cards are drawn from an ordinary deck of 52 playing cards. Find the probability of getting two pairs.( For example, the hand could be A-A-5-5-Q or 4-4-7-7-K)

跟帖(6)

dubious

2009-03-15 12:57:49

33.81% ?

ruby88

2009-03-15 13:02:43

回复:33.81% ?

gguyy

2009-03-15 19:14:42

回复:请教高中数学题

stephen7yu

2009-03-16 05:31:01

回复:回复:请教高中数学题

ruby88

2009-03-16 08:07:59

看错了, 答案应该是0.0475, 你是对的.

dubious

2009-03-16 00:28:42

嗯,gguyy的算法好像是对的,虽然和答案不一样;如果再加上