A policeman received information that a thief is at a distance of 1.5 km from him. The thief starts moving by car and the policeman chases him by car. The thief and the policeman are moving at the speeds of 90 km/h and 120 km/h respectively. At what distance (in km) will the police catch the thief?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 6 km.
Thief's speed = 90 km/h
Policeman's speed = 120 km/h
Relative Speed = 120km/h − 90km/h = 30km/h
the thief is 1.5 km ahead of the policeman
t = Distance/Relative Speed
⇒ 1.5km/(30km/h) = 0.05 hours
so
Distance = Speed × Time
⇒ 120 × 0.05 = 6km