The NY bound train traveled for 3 hours. 30*3 = 90 miles from D.C.
The D.C. bound train traveled for 1 hour. 1*50 = 50 miles from NY.
380 - (50+90) = 240 miles apart.
2. If the route is 380 miles from NY to DC, at what time will the trains pass each other?
The trains pass each other when they travel the distance between them (380 miles). Actually, the front ends of the trains reach each other when they travel that total distance, but for this problem that's considered passing.
D=RT
The trains are moving towards each other, so add their distances traveled (rt) together. The NY bound train travels for t hours, while the DC bound train travels for t-2 hours, since it left 2 hours later.
30t + 50(t-2) = 380
30t + 50t -100 = 380
80t = 480
t=480/80=6 hours. 6 hours from noon is 6PM.