Question

Bus A and Bus B leave the bus depot at 8 am.

Bus A takes 25 minutes to complete its route once and bus B takes 35 minutes to complete its route once.
If both buses continue to repeat their route, at what time will they be back at the bus depot together?
Assume the buses have no breaks in between routes.
Give your answer as a 12-hour clock time.

Answer 1

Explanation:

The lowest common multiple between 25 and 35 is found be splitting up into prime factors.

25: 5 * 5

35: 5 * 7

That means you need 2 fives and 1 y so that's 5 * 5 * 7 = 175 -- just 5 minutes short of 3 hours.

They both leave at 8:00 AM

Three hours later would be 11:00 AM

Five minutes short of that would be 10:55 AM