A thief running at 7 km/h is chased by a policeman whose speed is 12 km/h. If the thief is 280 m ahead of the policeman, then the time required for the policeman to catch the thief will be:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 3
Speed of the thief = 7 km/h
Speed of the policeman = 12 km/h
The thief is 280 m ahead of the policeman.
Time = Distance/Speed
⇒ Relative speed = (12 -7) = 5 km/h [since, running in the same direction]
⇒ Time = 280/(5 × 5/18) = 201.6 sec = 201.6/60 = 2016/600 = 3 216/600 = 3 9/25 minutes.