   SEARCH HOME Math Central Quandaries & Queries  Question from Aarti, a student: a theif running at 8 km/hr is chased by a policeman whose speed is 10km/hr.if the thief is 100 m ahead the policeman then what will b time required for the policeman to catch the thief? Based on the information, I assume the policeman and thief are moving in a straight line.

Imagine the policeman was chasing the thief at the same speed (say, 8 kilometers per hour).  Since the travel in the same direction, the two would always be the same distance apart.  Thus, to catch the thief, the policeman must travel faster.  Since the policeman travels 2 kilometers per hour faster than the thief, your question becomes,

"How long does it take to travel 100 meters at a (constant) rate of 2 kilometers per hour?"

Here you can use the formula

$V = \frac{d}{t}.$

Where V represents velocity (speed), d represents distance and t is time.  Watch your units!

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