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A thief is escaping along a straight road in a jeep traveling at 9 m/s. A policeman follows him on a motorcycle moving at 10 m/s. If the current distance between the jeep and the motorcycle is 100 m, after how much time will the policeman catch the thief?

1. 1 second
2. 19 second
3. 90 second
4. 100 second

Correct answer: 100 second

Solution

Closing speed = 10 - 9 = 1 m/s and the gap is 100 m, so time = 100/1 = 100 s.

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