An eastbound train and a westbound train meet each other on parallel tracks heading in opposite directions. The eastbound train travels 4 miles per hour faster than the westbound train. After 2.5 hours, they are 320 miles apart. At what speeds are the two trains traveling?
If the slower train has speed x, then the two are moving apart at speed x + x+4
So, since distance = speed * time,
(2x+4)*2.5 = 320