要考试了，问一道prep里的数学！

A hiker walking at a constant rate of 4 miles per hour ispassed by a cyclist traveling in the same direction along the same path at aconstant rate of 20 miles per hour. Thecyclist stops to wait for the hiker 5 minutes after passing her, while thehiker continues to walk at her constant rate. How many minutes must the cyclist wait until the hiker catches up?

(A) 6又2/3
(B) 15
(C) 20
(D) 25
(E) 26又2/3

金牌会员

Rank: 6 Rank: 6

精华: 0
积分: 2320
经验: 2320 点
威望: 251 点
金钱: 231 ￥
魅力: 231

2^#

michael_wind发表于 2011-1-24 20:47 | 只看该作者

是D吗？

TOP

金牌会员

Rank: 6 Rank: 6

精华: 0
积分: 2500
经验: 2500 点
威望: 249 点
金钱: 249 ￥
魅力: 249

3^#

zm_patrickS发表于 2011-1-25 06:56 | 只看该作者

(20-4)*5/60=距离
距离/4=1/3小时=20minutes

TOP

金牌会员

Rank: 6 Rank: 6

精华: 0
积分: 2960
经验: 2960 点
威望: 295 点
金钱: 295 ￥
魅力: 295

4^#

huangsiyan发表于 2011-1-26 06:46 | 只看该作者

答案是c

我看不太懂题目，能解释一下吗？谢谢~

TOP

金牌会员

Rank: 6 Rank: 6

精华: 0
积分: 1780
经验: 1780 点
威望: 197 点
金钱: 177 ￥
魅力: 177

5^#

zhangluE发表于 2011-1-28 20:41 | 只看该作者

“Thecyclist stops to wait for the hiker 5 minutes after passing her ” 要点是这一句！wait for the hiker 5 minutes after passing her 的意思是在pass her 5分钟后开始等hiker

TOP