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标题: 求解 为什么不是21中可能性呢 [打印本页]

作者: alice5678    时间: 2010-7-19 12:14
标题: 求解 为什么不是21中可能性呢
A certain restaurant offers 6 kinds of cheese and 2 kinds of fruit for its dessert platter.  If each dessert platter contains an equal number of kinds of cheese and kinds of fruit, how many different dessert platters could the restaurant offer?

8
12
15
21
27
作者: 姿姿不倦    时间: 2010-7-19 12:17
可以有两种cheese和两种水果。
也可以分别只有一种
作者: naturalwater    时间: 2010-7-19 12:30
各取一样+各取两样
C(2,1)C(6,1)+C(6,2)C(2,2)=27




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