A policeman saw a thief from distance of 150m and started running towards him. If speed of policeman and thief are 18 km/hr and 12 km/hr respectively, the distance covered by thief before he is being caught is:

300 m

         P                      T

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

                150 m

Speed (T) = 12km/h

Speed (P) = 18km/h

Relative speed = (18 - 12) km/h = 6km/h = 6 × \(\frac{5}{18}\) m/sec

Now,

Time = \(\frac{150}{{6} × \frac{5}{18}} \) = 90 sec

Distance (T) = 12 × \(\frac{5}{18}\) × 90 = 300 m