Question

A roofing company counted 65 invoices at the end of the month. They charge $490 for a new installation and $68 for a repair. The total dollar amount of the invoices was $10,750. How many new roofs were installed?

Answer 1

Answer:

There were 15 installments of the roof.

Step-by-step explanation:

We are given the following information in the question:

Total number of invoice = 65

Cost of installation = $490

Cost of repair = $68

Total cost = $10,750

Let x be the number of installments and y be the number of repairs.

Then, we can write the following equations:

$x + y = 65\\490x + 68y = 10750$

Solving the two equations in two variables, we get:

$68x + 68y = 4420\\490x + 68y = 10750\\490x - 68x = 10750 - 4420\\422x = 6330\\x = 15\\\text{Putting value of x in one of the equation}\\15 + y = 65\\y =65-15 = 50$

Thus, there were 15 installments and 50 repairs of the roof.