每盘棋下来，对手分不同，胜负不同， 棋手水平不同，最后的概率也不同

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56名棋手，在不考虑弃权的情况下，假 编排设定对过的对手不再相遇，一名男棋手在9场中对过全部4名女棋手的概率是?

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C4,4 * C5,52-1 / C9,56-1 = 2349060 / 733661775 = 0.003201829…

题解：

C9,56-1代表一名棋手在9轮比赛中的总概率

C4,4 为任意四轮比赛中的四名女选手

C5，52-1 代表一名棋手在9轮之中剩下的5论对到其他选手的概率　

所以此题结果约为千分之三点二，此题涉及排列组合

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