THE RATIO OF BUSES TO CARS CAN BE EXPRESSED AS 2X
1. The ratio of buses to cars can be expressed as 2x: 23x. We can
write an equation that represents the fact that there are 630 fewer
buses than cars: 2x + 630 = 23x.
Solving this equation for x yields the following:
2x + 630 = 23x
630 = 21x
30 = x.
There are 23x cars on River Road which equals 23 × 30 = 690 cars.
The correct answer is D.