GWD 第四套 Q5

mereimoun

A certain club has 20 members. What is the ratio of the member of 5-member committees that can ne formed from the members of the club to the number of 4-member committees that can ne formed from the members of the club?

A) 16 to 1
B) 15 to 1
C) 15 to 5
D) 15 to 6
E) 5 to 4

My answer is 1:5... Haiz... dun know how to tackle this problem!!!

mereimoun

我可以问问一个很傻的问题么，c(5,20):c(4,20)。。。这个是什么意思？c(5,20):c(4,20)。。。

vevelay

c(5,20):c(4,20)=16:5

mereimoun

A) 16 to 1
B) 15 to 1
C) 16 to 5
D) 15 to 6
E) 5 to 4

对不起对不起，答案是16:5，为什么阿，望指教！

vevelay

楼主，你的答案有错误吧，应该是16：5
20个里面选5个：20个里面选4个，楼主再想想