Question

The Greyhound bus going to Michigan leaves the station every 20 minutes. Another bus going to Arkansas leaves the station every 40 minutes. If it is 10:40 a.m., what will be the first time both Greyhound buses leave the station at the same time?

Answer 1

The first time both Greyhound buses leave the station at the same time will be at 11:20 a.m.

Step-by-step explanation:

To find the first time both Greyhound buses leave the station at the same time, we need to find the least common multiple (LCM) of 20 minutes and 40 minutes, which is the smallest multiple that they both share. The LCM of 20 and 40 is 40 minutes.

Since it is currently 10:40 a.m., the next time that is a multiple of 40 minutes is at 11:20 a.m. This will be the first time both Greyhound buses leave the station at the same time.

The first time both Greyhound buses leave the station at the same time will be at 11:20 a.m.

Answer 2

The Greyhound bus going to Michigan leaves the station every 20 minutes.

it's 10:40

so next departure on 10:60 => 11:00 then 11:20 then 11:40...

Another bus going to Arkansas leaves the station every 40 minutes.

it is 10:40

so next departure on 11:20 then 12:00

=> 11:20