Xiao Ming and Xiao Hua practice running on the 400 meter track. They start at the same time and run in the same direction. After 200 seconds, Xiao Ming catches up with Xiao Hua. They run in the opposite direction and meet each other after 40 seconds. What's their speed per second?

Xiao Ming and Xiao Hua practice running on the 400 meter track. They start at the same time and run in the same direction. After 200 seconds, Xiao Ming catches up with Xiao Hua. They run in the opposite direction and meet each other after 40 seconds. What's their speed per second?


A: Xiaoming travels 6 meters per second, Xiaohua travels 4 meters per second



Xiaoming and Xiaohua are running on a 400 meter circular track. They start from the same point and walk in the same direction. Xiaoming runs 3.5 meters per second and Xiaohua runs 5.5 meters per second
How many seconds have two people met for the second time?


The second time we met, Xiaohua ran one more lap than Xiaoming. The distance was 400
Speed difference 2
Time = 400 / 2 = 200



The circumference of the circular track in the school sports ground is 400 meters, and Xiaohua's running speed is three times that of Xiaohong. If they start from the same starting point along the track in the same direction at the same time, and Xiaohua meets Xiaohong for the first time five minutes later, what is Xiaohong's running speed?


3 × 5 = 15 (min)
15 + 5 = 20 (minutes)
20÷5=4
400 △ 4 = 100m