數學 速率問題

她跑步的平均速率
= 324米 × 5 / 10 分鐘
= 1620米 / 10分鐘
= 1620米 / (10 × 60) 秒
= 1620米 / 600秒
= 2.7 米每秒

2008-04-13 22:56:59 補充：
The concept of 002 is wrong because he/she should not do cancelling in a fraction with different units in the denomenator and numerator.

(324x5)m/10min
=1620m/10min
=162m/1min
=162m/60s
=2.7m/s