24.
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?
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没看错的话,搭配只有一种水果+一种cheese或者两种水果+两种fruits吧
所以应该C(2,1)*6+C(2,2)*C(6,2)=27
思路和你一样,但是我的答案为什么和你不一样?
C(2,1)*C(6,1)+C(2,2)*C(6,2)=2*6+2*6*5=72
sorry,i was stupid.
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