One car travels 400 miles in the same amount of time it takes a second car traveling 10 miles per hour slower than the first to go 350 miles. What are the speeds of the cars?
A)65 mph; 55 mph
B)80 mph; 70 mph
C)85 mph; 75 mph
D)70 mph; 60 mph
E)100 mph; 90 mph

Question

Quizplus · Accepted Answer

The first car travels 400 miles, and the second car travels 350 miles at a speed 10 mph slower. If we let the speed of the first car be x mph, then the second car's speed is (x - 10) mph. The time taken by both cars is the same, so 400/x = 350/(x - 10). Solving this equation gives x = 80 mph for the first car and 70 mph for the second car.

One Car Travels 400 Miles in the Same Amount of Time