A,B AND C starts cycling around a circular path in the same direction at same time. Circumference of the path is 360km. If the speed of A is 40m/min, speed of B is 60m/min and that of C is 72m/min and they start from the same point, then after what time interval they will be together at the starting point?
the speed of A = 40 m/min
time taken to complete one circle = 360/40 = 9 min.
the speed of B = 60m/min
time taken to complete one circle = 360/60 = 6 min
the speed of C = 72 m/min
time taken to complete one circle = 360/72 = 5min.
LCM of 9, 6 , 5 is 90 min.
therefore after 90 min they will be together at starting point.
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