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

Explanation:

p = power washer and g = generator

6p + 6g = 90 .....multiply by 4

4p + 8g = 100 ....multiply by -6

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24p + 24g = 360 (result of multiplying by 4)

-24p - 48g = -600 (result of multiplying by -6)

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-24g = - 240

g = -240 / -24

g = 10 <=== the generator cost $ 10 per hr

6p + 6g = 90

6p + 6(10) = 90

6p + 60 = 90

6p = 90 - 60

6p = 30

p = 30/6

p = 5 <==== the power washer costs $ 5 per hr

check...

4p + 8g = 100

4(5) + 8(10) = 100

20 + 80 = 100

100 = 100 (correct)