Q:

**Sol : **(length of train+ length of bridge) = speed of train x Time

(250+150) = 20 x Speed

Speed = 400/20= 20 m/s =72 km/h

Q:

**Sol : **(length of train+ length of bridge) = speed of train x Time

(250+150) = 20 x Speed

Speed = 400/20= 20 m/s =72 km/h