Multiple choice

Four trains pass nearby metro stations at intervals of 3, 6,12 and 14 minutes. If they all meet at 10:00 am on a station, at what time will they meet again in one of the metro stations after 10:00 am?

  1. 10:30 am

  2. 11:24 pm

  3. 11:24 am

  4. 11:30 am

  5. 11:30 pm

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The trains will meet again after an interval, which is a lowest common multiple of 3, 6, 12 & 14. Therefore, L.C.M of 3, 6, 12 & 14 = 2 x 2 x 7 x 3 = 84 84 minutes = 1 hour & 24 minutes Hence, the trains will meet again at 10 + 1.24 = 11:24 am