Answer:
After 4 hours the trains will be 600 miles part.
Explanation:
Two trains leave the same station at the same time, but are headed in opposite directions. One train travels at 70 mph and the other train travels at 80 mph.
Velocity of train 1 = 70 mph
Velocity of train 2 = 80 mph
Since the velocities are in opposite direction
Relative velocity = 70 + 80 = 150 mph
We need to find when the trains will be 600 miles apart.
We have
Distance = Time x Velocity
600 = Time x 150
Time = 4 hours
After 4 hours the trains will be 600 miles part.