A, B, and C start running simultaneously, starting from a point, around a circular track of length 900m, with respective speeds of 3m/s, 5m/s, and 6m/s. A and B run in the same direction while C runs in the opposite direction of the other two. After how much time will they meet for the first time?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 3 i.e. 15 minutes.
Total length of the track = 900 m
Speed of A, B, and C = 3m/s, 5m/s, and 6m/s
Relative speed of A and B = Speed of A - Speed of B = 2 m/s
Time = 900/2 = 450 sec
Relative speed of A and C = Speed of A + Speed of C = 3 m/s
Time = 900/3 = 300 sec
All of them will meet = L.C.M(450 and 300) = 900/60 = 15 minute