Question

A, B and C start at the same time in the same direction to run around a circular stadium. A completes a round in 252 seconds, B in 308 seconds and C in 198 seconds, all starting at the same point . After what time will they meet again at the starting point?

• A. 26 minutes 18 seconds
• B. 42 minutes 36 seconds
• C. 45 minutes
• D. 46 minutes 12 seconds
• E. 50 minutes

Answer 1

The correct option is

D

46 minutes 12 seconds

A, B and C will come back to the starting point at the multiples of 252, 308 and 198 sec respectively. Thus, all the three meet at the start only at the common multiples of 252, 308 and 198 sec.

L.C.M of 252, 308 and 198 = 2772.

So, A, B and C will again meet at the starting point in 2772 sec. i.e., 46 min 12 sec.