Question

Residents of the town of Maple Grove who are connected to the municipal water supply are billed a fixed amount monthly plus a charge for each cubic foot of water used. A household using 1100 cubic feet was billed $114, while one using 1500 cubic feet was billed $130.
What is the exact charge per cubic foot?

Answer 1

Answer:

The exact charge per cubic foot of water usage is 4 Cents.

Step-by-step explanation:

Let the per cubic foot charge be $ 'x' and the fixed charge be $ 'y'.

A household using 1100 cubic feet was billed $ 114.

Therefore, we get the equation,

$1100 x + y = 114$.......( A )

And other household 1500 cubic feet was billed $ 130.

Therefore, we get the equation,

$1500 x + y = 130$ ......( B ).

Now, we subtract equation A from  equation B.

$1500 x + y = 130$.....( B )

$1100 x + y = 114$ ......( A )

__________________

So, we get,

$400 x = 16$.

Therefore,

$x = \frac{16}{400}$

$x = 0.04 = 4$ Cents.

So, the exact charge per cubic foot is 4 Cents.