A thief was spotted by a policeman at a distance of 1200

Solution

Here, thief ran 6.4 km in 52 minutes i.e. (52/60) hours (As 1 hour = 60 minutes) Speed of the thief = Distance/Time 6.4/ (52/60) = 6.4 x 60/52 = 96/13 km/h Now, a policeman ran 6.4 km in 40 minutes = 40/60 hours Speed of the policeman Distance/ Time =6.4 x 60/40 = 48/5 km/h As a policeman chases a thief.   Hence, they run in the same direction Relative speed when running in the same direction =48/5-96/13=144/65 Now, the time taken by a policeman to cover 1200m, 1200/1000 = 1.2km distance Now, the required distance for a thief, Speed x Time = 96/13 x 13/24 =96/24= 4 km Hence, the thief had to run 4 km before he was caught.