10 PM is 6 hours after 4 PM and 2 hours after 8 PM 1st train's speed is r mph 2nd train's speed is r+112 mph Make a chart: |rate |time |distance| 1st train at 10 PM | r | 6 | 6r | 2nd train at 10 PM |r+112| 2 |2(r+112)| Set the distances equal.Solve that for r and you'll get r = 56 mph for the 1st train. Add 112 to 56 and you'll get 168 mph for the 2nd train. Can a train go that fast? Could it stay on the rails? LOL Edwin