ChaseDream
搜索
返回列表 发新帖
查看: 410|回复: 1
打印 上一主题 下一主题

tt-5-28

[复制链接]
楼主
发表于 2009-1-31 19:55:00 | 只看该作者

tt-5-28

不知解法,盼牛牛指点

Q28:

Last Sunday a certain store sold copies of Newspaper A for $1.00 each and copies of Newspaper B for $1.25 each, and the store sold no other newspapers that day.  If r percent of the store’s revenues from newspaper sales was from Newspaper A and if p percent of the newspapers that the store sold were copies of newspaper B, which of the following expresses r in terms of p?

 

A.    100p / (125 – p)

B.     150p / (250 – p)

C.     300p / (375 – p)

D.    400p / (500 – p)

E.     500p / (625 – p)

Answer:
沙发
发表于 2009-1-31 20:25:00 | 只看该作者
  答案选D,小弟用的是特殊值法,100 copies A, 100 copies B,so A等于50, B的revenue是100除225,so r等于100/225*100(因为是percent),所以带进出找,一看就是D了~
您需要登录后才可以回帖 登录 | 立即注册

Mark一下! 看一下! 顶楼主! 感谢分享! 快速回复:

手机版|ChaseDream|GMT+8, 2025-9-4 13:58
京公网安备11010202008513号 京ICP证101109号 京ICP备12012021号

ChaseDream 论坛

© 2003-2025 ChaseDream.com. All Rights Reserved.

返回顶部