gwd-5-6,12

apple1

gwd-5-Q6:

A certain company assigns employees to offices in such a way that some of the offices can be empty and more than one employee can be assigned to an office. In how many ways can the company assign 3 employees to 2 different offices?

A. 5

B. 6

C. 7

D. 8

E. 9

这题我不明白是什么意思，请求赐教！

GWD－5－Q12:

If r, s, and w are positive numbers such that w = 60r + 80s and r + s = 1, is w < 70?

(1) r > 0.5

(2) r > s

答案：D；我选：E

请教这题的思路！

apple1

thanks    a    lot  !!!

girls

ding!!!!!!

himba

第一题：每个人可能分到office 1或office 2，所以每个人有两种分配可能，三人共2*2*2=8种可能

第二题：因为r+s=1，所以条件一和条件二等价.w=60r+80-80r=80-20r，若r>0.5，推出w<70