Two trains leave the station at the same time, one heading west and the other heading east. the westbound train travels at 65 miles per hour. the eastbound train travels at 85 miles per hour. how long will it take for the two trains to be 390 miles apart

Hour one:

Eastbound train- 65 mi
Westbound train- 85 mi

150 miles apart

Hour two:

Eastbound train- 130 mi
Westbound train- 170 mi

300 miles apart

Eastbound train travels 32.5 miles in 30 min, Westbound train travels 42.5 miles in 30 min

Two and a half hours:

Eastbound train- 162.5 mi
Westbound train- 212.5 mi