A policeman saw a thief from distance of 300m and started running towards him. If speed of policeman and thief are 18 km/hr and 9 km/hr respectively, the distance covered by thief before he is being caught is:

300 m

         P                      T

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

                300 m

Speed (T) = 9km/h

Speed (P) = 18km/h

Relative speed = (18 - 9) km/h = 9km/h = 9 × \(\frac{5}{18}\) m/sec

Now,

Time = \(\frac{300}{{9} × \frac{5}{18}} \) = 120 sec

Distance (T) = 9 × \(\frac{5}{18}\) × 120 = 300 m