A person sees another person snatching a chain from a lady, at a distance of 300 metres. He starts running and catches the thief by running at 10 km/h after running a total distance of 1.5 km. The speed at which the thief was running was:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 8 km/h.
Time taken by person to cover 1.5 km = 1.5/10 = 0.15 h
⇒ 0.15 × 60 × 60 = 540 sec
Let the speed of the thief be x m/sec.
Speed of person = 10 × 5/18 = 25/9 m/sec
Distance covered by thief = 1500 - 300 = 1200 m
Speed of thief = 1200/540
⇒ (20/9) × (18/5) = 8 km/h