There is a circular path around a sports field. Sonia takes 18 minutes to drive one round of the field, while Ravi takes 12 minutes for the same. Suppose they both start at the same point and at the same time and go in the same direction. After how many minutes will they meet again at the starting point?

Question – There is a circular path around a sports field. Sonia takes 18 minutes to drive one round of the field, while Ravi takes 12 minutes for the same. Suppose they both start at the same point and at the same time and go in the same direction. After how many minutes will they meet again at the starting point?

Solution:

Time taken by Sonia  = 18 minutes

Time taken by Ravi = 12 minutes

To find the required time we have to find the LCM of these two times which they take to drive one around.

18 = 2 × 3 × 3

12 = 2 × 2 × 3.

LCM (18, 12) = 2 × 2 × 3 × 3 = 36

Hence, after 36 minutes they will meet again.

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