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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? A. 8
B. 12
C. 15
D. 21
E. 27 选择E 既然有相同水果,是不是分为三种奶酪和一种水果一盘。我的结果是2*6!/(3!*3!)=40. 我错在哪里了?
A. 8
B. 12
C. 15
D. 21
E. 27 选择E 既然有相同水果,是不是分为三种奶酪和一种水果一盘。我的结果是2*6!/(3!*3!)=40. 我错在哪里了? |
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