A thief is noticed by a policeman from a distance of 92 m. The thief starts running and the policeman chases him. The thief and the policeman run at the speed of 90 km/h and 104.4 km/h, respectively. In how much time will the policeman catch the thief?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 23 seconds.
Convert Speeds to m/s
1 km/h = 5 / 18 m/s
⇒ 90 × 5 / 18 = 25 m/s
Speed of the policeman :
⇒ 104.4 × (5/ 18) = 29 m/s
The Relative Speed
⇒ 29 - 25 = 4 m/s
Time = Distance / Relative Speed = 92 / 4 = 23 seconds
The policeman will catch the thief in 23 seconds .