Meg and Bob are
among the 5 participants in a cycling race.
If each participant finishes the race and no two participants finish at
the same time, in how many different possible orders can the participants
finish the race so that Meg finishes ahead of Bob?<--[if !supportLists]-->
A. 24
B. 30
C. 60
D. 90
E. 120
the answer is C,why?作者: himba 时间: 2005-6-4 13:15
P55/2=60.因为这俩哥们，不是他先就是她先，所以把5个人一排列，再除2就行了。
想通了就很容易的。
作者: bfghdggf 时间: 2005-6-6 06:59
通了，谢谢◎！[em07][em07]
欢迎光临 国际顶尖MBA申请交流平台--TOPWAY MBA (http://forum.topway.org/)
