Mathematics for IGCSE & O level - Number (Section 3 - No. 4)

If two lighthouses flash every 22 and 16 seconds, at what time will they flash together again if they flashed at 10 pm?

10:02:40

10:03:00

10:04:48

10:05:12

176 seconds, the LCM, which converts to 2 minutes and 56 seconds. 10:00:00 + 00:02:56 = 10:02:56