The total cost to paint this wall once is $16 and this can be determined by using the unitary method.
Given :
Each quart of paint costs $8 and covers 90 square feet.
The following steps can be used in order to evaluate the total cost required to paint the wall once:
Step 1 - The unitary method can be used in order to determine the total cost required to paint the wall once.
Step 2 - According to the given data, one quart covers 90 square feet area so to cover the 180 square feet area it requires:
[tex]=\dfrac{180}{90}[/tex]
= 2 quart
Step 3 - According to the given data, if one quart cost $8 then the cost of 2 quarts of paint is:
[tex]=2\times 8[/tex]
= $16
So, the total cost to paint this wall once is $16.
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https://brainly.com/question/24406804
