If m boys and n girls,answer is (m-1)/(m+n-1)

来源: jinjing 于 2010-05-30 08:35:27 [] [旧帖] [给我悄悄话] 阅读数 : (42 bytes)
回答: 概率题 由 康MM 于 2010-05-27 05:38:05

Word question should give some conditions.

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