RRB RPF RPSF SI and CONS Model Papers 4 with solutions

Question : 72 of 122

Marks: +1, -0

A thief stole a purse and ran away. He was spotted by a policeman from a distance of 400 m. When the policeman started chasing, the thief also started running. Assume the speed of the thief as 10 km/h and that of the policeman as 15 km/h. How far the thief will have run before he is overtaken?

400 m
1500 m
1200 m
800 m

Validate

Solution:

(4) The distance between the policeman and the thief = 400 m
Speed of the policeman = 15 km/h

=15 ×{5}/{18}= {75}/{18} {m} \/ {s}

Speed of the thief = 10 km/h

=10 ×{5}/{18}= {50}/{18} {m} \/ {s}

Let the distance between the thief and the point where the policeman overtakes the thief be x m.
∴

{400+x}/{\text"Speed of policeman"} = {x}/{\text"Speed of thief "}

⇒{18(400+x)}/{75}=\ {18 x}/{50}

⇒ 50(7200+18 x)=75× 18 x

x=800 m

Go to Question:

Prev Question

Next Question