In how many ways may a group of 5 men be chosen from a squad of 9? In how many of these will two particular men appear?
first ques has been solved. i need the second one. thx
combination
2010-03-16 10:07 am
回答 (2)
2010-03-16 12:10 pm
✔ 最佳答案
As two particular men should appear in the 5-men group,That equals to you have only 3 free seat that chosen from the remaining 7 people, so that is 7C3.
2010-03-16 4:41 pm
1st Q: 9C5 = 126
2nd Q: 9C5 - 7C3 = 126 - 35 = 91
2nd Q: 9C5 - 7C3 = 126 - 35 = 91
收錄日期: 2021-04-23 18:25:26
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100316000051KK00162