Question

An airport offers two shuttles that run on different schedules if both shuttles leave the airport at 4:00 pm at what time will they next leave the airport together?

Answer 1

The lowest common multiple of the two (LCM) is found by simply seeing the multiples of 9 and 6 and seeing if they match up. 6 is not a factor of 9, so that doesn't work. The next multiple of 9 is then 18, and 6 is a factor of 18 too, so 4:18 would be your time