A policeman follows a thief, who is 150 metres ahead of him, and they run at the speed of 6 km/h and 5 km/h, respectively. What distance does the policeman cover to catch up with the thief?
900 metres
Relative speed of the policeman = (6 - 5) km/h = 1 km/h
Convert to m/s: (1 × 1000) ÷ 3600 = 5/18 m/s
Time taken to catch the thief = 150 ÷ (5/18) = (150 × 18) ÷ 5 = 540 seconds
Distance covered = Speed × Time = 6 km/h × (540/3600) h
Distance = 6 × (540/3600) × 1000 = 900 metres
Thus, the correct answer is 900 metres.
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