The length of train a and train B are 144m and 180m, and train a runs 4m more per second than train B. the two trains are facing each other, and it takes 9s from meeting to staggering. What's the speed of the two trains?

The length of train a and train B are 144m and 180m, and train a runs 4m more per second than train B. the two trains are facing each other, and it takes 9s from meeting to staggering. What's the speed of the two trains?

Suppose car B travels XM per second, then car a Travels (x + 4) m per second. According to the meaning of the question, we get: 9 (x + X + 4) = 144 + 180, sort out: 2x = 32, solve: x = 16, then car a travels 20m per second, car B travels 16m per second

We need to use the equation
If train a is 225 meters long, 25 meters per second, and train B is 20 meters per second, the time for train a and train B to miss is 9 seconds. How long is train B? How many seconds does it take for Xiao Ming on train a to see train B pass?

Let the length of train B be X. it took Xiao Ming y seconds to see train B pass
The equation x + 225 = (25 + 20) * 9 gives x = 180m
180 = (25 + 20) * y, y = 4S