A policeman saw a thief from distance of 300m and started running towards him. If speed of policeman and thief are 15 km/hr and 12 km/hr respectively, the distance covered by thief before he is being caught is:

1.2 km

         P                      T

         Ι------------------Ι---------------Ι

                300 m

Speed (T) = 12km/h

Speed (P) = 15km/h

Relative speed = (15 - 12) km/h = 3km/h = 3 × \(\frac{5}{18}\) m/sec

Now,

Time = \(\frac{300}{{3} × \frac{5}{18}} \) = 360 sec

Distance (T) = 12 × \(\frac{5}{18}\) × 360 = 1200 m = 1.2 km