A thief saw a policeman and he started running at a speed of 12 m/s. After a certain time, the policeman starts running behind the thief at a speed of 18 m/s. If the policeman covered a 540 m distance to catch the thief, the time (in seconds) after which the policeman started running is:
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. 15.
Time taken by the policeman = = 30 seconds
Thief runs in 30 seconds = 12 × 30 = 360 m
Gap = 540 – 360 = 180 m
Time before = = 15 seconds