Question

A thief is noticed by a policeman from a distance of 200 m. The thief starts running and the policeman chases him. The thief and policeman run at the rate of 10 km/hr and 11 km/hr respectively. At what distance will the policeman catches the thief?
1. 2 km
2. 2.2 km
3. 2.4. km
4. 2.6 km

Answer 1

Correct Answer - Option 2 : 2.2 km

Given: 

The speed of thief is 10km/hr

Distance between thief and policeman is 200m 

Formula Used: 

Relative speed = speed of one person - speed of 2nd person (when moving in same direction) 

Distance = speed × time 

Calculation: 

Relative speed,

⇒ 11 - 10 = 1 km/hr 

Time taken by policeman to chase thief,

⇒ 200m/(1 × 5/18)m/s = 720 seconds  

Distance covered by a policeman in 720 seconds to chase thief,

⇒ 11 × 5/18 × 720 = 2200 m = 2.2 km 

∴ Distance covered by a policeman  to chase thief is 2.2 km.