作者thank1984 (thankakimo)
看板Grad-ProbAsk
标题[理工] 离散-组合
时间Sun Mar 22 17:59:15 2009
题目:A committee of six is to be made from four students and eight teachers.
How many ways can the followings be done??
a) If the committee contains exactly three students?
b) If the committee contains at least three students?
问题: 请问各位大大这题要怎麽解呢?? 烦请解答 感谢
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◆ From: 122.116.171.19
1F：推 dasmond:就排列组合阿 ~''~ 03/22 18:24
2F：→ thank1984:a)是4取3 * 8取3? b)是 12取6 - 8取6 - 4取1*8取5 - 03/22 18:28
3F：→ thank1984:4取2*8取4?? 03/22 18:28
4F：推 s987692:a.c(4,3)*c(8,3) b. c(4,3)*c(8,3)+c(4,4)*c(8,2) 03/22 19:46
5F：→ thank1984:嗯嗯 感谢S大解答 03/22 20:36