题目内容双击单词支持查询和收藏哦～
收藏
纠错
Working together, 7 identical pumps can empty a pool in 6 hours. How many hours will it take 4 pumps to empty the same pool?
-
A.$$4·(\frac{2}{3})$$
-
B.$$9·(\frac{1}{4})$$
-
C.$$9·(\frac{1}{3})$$
-
D.$$9·(\frac{3}{4})$$
-
E.$$10·(\frac{1}{2})$$
E显示答案
