作者newacc (XD)
看板juniorhigh
标题Re: [问题] 请问一题数学
时间Thu Oct 8 00:24:34 2009
※ 引述《lovekyoko (我在Tamap 天气晴)》之铭言：
: Two water pumps, working simultaneously at their respective constant rates,
: took exactly 4 hours to fill a certain swimming pool. If the constant rate
: of one pump was 1.5 times the constant rate of the other, how many hours would
: it have taken the faster pump to fill the pool if it had worked alone at
: its constant rate?
: 答案是 20/3
: 请问这题要怎麽算 谢谢
需要中译吗.....
(以下...呃...我意思有到就对了,阿字眼对不对就不知道了XD)
两个水帮浦,同时各自等速运作,需要四小时才能把一个游泳池灌满.
如果一台帮浦的速度是另一台帮浦的1.5倍.
试问若用较快的帮浦,需要花多少时间才能将这一个泳池填满?
令慢者为X 则快者为1.5X
设泳池总水量为L
欲求 : L / 1.5X
L / ( X + 1.5X ) = 4
L = 4 * 2.5X
L = 10X
L / 1.5X = 10X / 1.5X = 20/3
#
--
※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 140.112.240.3
※ 编辑: newacc 来自: 140.112.240.3 (10/08 00:25)