Question

A thief is running on a train with 12km/hr .the police car

Is moving with 80 km /h.if the train is 60km/h .what is the speed of the thief w.r.t police car?

Answer 1

Speed of thief wrt ground = speed of train wrt ground(60)+speed of thief wrt train(12)
=60 km/hr+ 12 km/hr = 72 km/hr
speed of police car = 80 km/hr
speed of thief w.r.t police car = 72-80 km/hr = -8km/hr