Why do this
problem?
This problem is one to use when relating time and distance and
especially when looking at timetables and the $24$ hour clock.
Timetables are tricky things and they sometimes need careful
thinking to make sense of them. There are many conventions involved
in their presentation and learners may need help in finding the
meanings in them.
Key questions
Have you drawn a diagram of the buses on the road from A to
B?
How many buses are on the road at $0600$?
How many buses are on the road at $0620$, $0640$, $0700$ and
so on?
Do you understand how the $24$ hour clock works?
Possible extension
Learners could find out bus times from a local timetable and
even make up their own problem about them.
Possible support
Suggest starting by drawing a picture all the coaches on the road
at various times.