think easier 回复：The answer is 32

来源: 于 2010-08-16 22:21:54 [旧帖] [给我悄悄话] 本文已被阅读：次

view a pair as a single person, so we have c(3,4) but each pair can offer 2 choices. so tatol is c(3,4)*2*2*2*2 = 32.