Question

For every 2 red cars there are 3 blue cars in the dealership. If there are 535 cars, how many red cars are there? How many blue cars are there?

Answer 1

r = red cars

b = blue cars

The ratio of the number of red cars to the number of blue cars is 2 to 3

r / b = 2 / 3

Cross multiply

3 r = 2 b

Divide both sides by 3

r = 2 / 3 b

The sum of the number of red cars and the number of bue cars is 535.

r + b = 535

Replace r with 2 / 3 b in this equation.

2 / 3 b + b = 535

2 / 3 b + 3 / 3 b = 535

5 / 3 b = 535

Multiply both sides by 3

5 b = 1605

Divide both sides by 5

b = 321

r = 2 / 3 b = 2 ∙ 321 / 3 = 642 / 3 = 214

There are 321 blue cars and 214 red cars.