A policeman notices a thief from a distance of 300m. The thief starts running and the policeman chases him. The thief and the policeman run at speeds of 10km/h and 12km/h, respectively. What will be the distance between them (in m) after 6 minutes?

1. Relative Speed: Since both are running in the same direction:
Relative Speed=Speed of Policeman−Speed of Thief
Relative Speed=12km/h−10km/h=2km/h
Convert Relative Speed into meters per minute or meters per second:

Relative Speed=2×
18
5
​
m/s=
9
5
​
m/s
Time given =6 minutes=6×60=360 seconds.

Distance covered relative to each other in 6 minutes:

Distance Covered=Relative Speed×Time
Distance Covered=
9
5
​
×360=5×40=200m
Remaining distance between them:

Initial Distance=300m
Distance after 6 minutes=300m−200m=100m