A thief is spotted by a policeman from a distance of 200 metres. When the policeman starts the chase, the thief also starts running. If the speed of the thief is 9 km/h and that of the policeman 10 km/h, how far will the thief have to run before he is overtaken?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 1.8 km.
The speed of the policeman = 10 km/h
The speed of the thief = 9 km/h
Relative speed = 10 - 9 = 1 km/h = 5/18 m/sec
Total distance to be covered = 200 m
Time required to catch the thief = 200/(5/18) = 720 sec = 1/5 hour
Distance covered by thief = 9 × (1/5) = 9/5 = 1.8 km
Therefore, the thief will have to run 1.8 km.