Question

Nate rented a power washer and a generator. On his first job, he used each piece of equipment for 6 hours which cost $90. On his second job, he used the power washer for 4 hours and the generator for 8 which cost $100. What's the hourly cost of each piece of equipment?

Answer 1

Answer: the hourly cost of renting a power washer is $5

the hourly cost of renting a generator is $10

Explanation:

Let x represent the hourly cost of renting a power washer.

Let y represent the hourly cost of renting a generator.

On his first job, he used each piece of equipment for 6 hours which cost $90. This means that

6x + 6y = 90 - - - - - - - - 1

On his second job, he used the power washer for 4 hours and the generator for 8 which cost $100. This means that

4x + 8y = 100 - - - - - - - - - - 2

Multiplying equation 1 by 4 and equation 2 by 6, it becomes

24x + 24y = 360

24x + 48y = 600

Subtracting, it becomes

- 24y = - 240

y = - 240/-24 = 10

Substituting y = 10 into equation 1, it becomes

6x + 6 × 10 = 90

6x + 60 = 90

6x = 90 - 60 = 30

x = 30/6 = 5