Board logo

标题: prep数学24 [打印本页]

作者: cyvivi    时间: 2011-8-30 06:55     标题: prep数学24

24.     
In a certain game, the units of currency of three countriesare the crown, the shield, and the pound, respectively.  If 2 crowns equal 3 shields and 3 shieldsequal 4 pounds, how many crowns equal 18 pounds?

(A)  9
(B) 16
(C) 18
(D) 32
(E) 36
------------------------------------------------------------------------------------------------------------------------------------
【答案】A

【思路】2c=3s,3s=4p
       4p=18,p=4.5
       3s=18,s=6
       代入2c=3s,c=9



为什么是4p=18?不应该是p=18吗?
作者: vansonkated    时间: 2011-8-30 20:44

题目问:how many crowns equal 18 pounds?

2 crowns equal 3 shields and 3 shields equal 4 pounds

也就是说2 crowns equal 4 pounds
用比例法:2/4= X/18  求得X=9




欢迎光临 国际顶尖MBA申请交流平台--TOPWAY MBA (http://forum.topway.org/) Powered by Discuz! 7.2