Answer:
5:40
Step-by-step explanation:
This is a problem involving the least common difference.
If you know that the red and blue trains left at the same time at 5, you know that another red train will leave at 5:08. Another blue train at 5:10.
The way to solve this will be to write out the factors of 8 and 10 and find the smallest number that they overlap.
Red:
8, 16, 24, 32, 40, 48, 56, 64, 72, 80
Blue:
10, 20, 30, 40
You see that after 40 mnutes, they are both leaving the station again. After 40 minutes, at 5:40, they are both leaving.
