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

答案为20，可我横算竖算是25啊

[(20/60)*5]/(4/60)不是等于25嘛？

谢谢~

你忽略了一个事实，那就是在cyclist骑车的同时，hiker也在走路，所以答案是25-5=20。