If a committee of 3 people is to be selected from among 5 married couples so that the committee does not include two people who are married to each other, how many such committees are possible?
A. 20
B. 40
C. 50
D. 80
E. 120
我选的D, 不知道对不对
第一步,从5对couple里选3对
第二步,3对中每对选1个人
这样就可以保证选出的人中没有夫妻了
C(5,3)*C(2,1)*C(2,1)*C(2,1)=10*8=80
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