Two trains leave the station at the same time, one heading west and the other east. The westbound train travels at 80 miles per hour. The eastbound train travels at 90 miles per hour. How long will it take for the two trains to be 476 miles apart?

2.8 hours

Step-by-step explanation:

Distance = rate * time

If the west-bound train travels at a rate of 80 mph for t hours, then the distance it travels is 80t.

If the east-bound train travels at a rate of 90 mph for t hours, then the distance it travels is 90t.

The distance between the trains after t hours is 476; therefore, the distance of the west-bound train plus the distance of the east-bound train equals the total distance between them, 476:

80t + 90t = 476 and

170t = 476 so

t = 2.8 hours