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

Correct option is B

Given:

Time taken by A to complete a round = 252 seconds,
Time taken by B to complete a round = 308 seconds,
Time taken by C to complete a round = 198 seconds.

Formula Used:
To find when they will meet again at the starting point, we need to calculate the least common multiple (LCM) of the times taken by A, B, and C.

Solution:
The LCM of 252, 308, and 198.
Prime factorization:
​$$252 = 2^2 \times 3^2 \times 7 \\\\ \\308 = 2^2 \times 7 \times 11 \\\\ \\198 = 2 \times 3^2 \times 11\\$$​​
LCM = $$2^2 \times 3^2 \times 7 \times 11 = 2772 \text{ seconds}$$ 

= $$\frac{2772}{60} = 46 \ minutes 12 \ seconds$$​​
Thus, A, B, and C will meet again at the starting point after $$\frac{2772}{60} = 46 \ minutes 12$$​seconds.