GRE®
返回
Question 12 Selected one answer choice
收藏
笔记
反馈
我的笔记
5000
保存
1 2 3 4 5 6 7 8 9 10 11 12 13 14
If it takes Daniel 9 hours to clean an office building and it takes Mark 6 hours, how long would it take the two of them, working together, to clean the building?

A.3 hours

B.3 hours 36 minutes

C.4 hours 45 minutes

D.6 hours

E.7 hours 30 minutes

我的答案：