Question

The siding of a house is 2250 square feet. The siding needs two coats of paint. One quart costs $18 and covers 80 square feet. One gallon costs $29 and covers 320 square feet. What is the minimum cost of the paint needed to complete the job? How much paint is left over?

Answer 1

Answer:

Minimum cost needed = $221

Remaining quart paint = 7/8

Step-by-step explanation:

Let

x = number of 1 gallon paints

y = number of 1 quart paints

1 gallon covers 320 square feet

1 quart covers 80 square feet

Number of gallons paint needed = Total siding of the house / 320 square feet

= 2250 / 320

= 7.0312

Approximately to the nearest whole number

Number of gallons paint needed = 7 gallons

Total siding of the house covered by gallons = 7 gallons × 320 square feet

= 2,240 square feet

Siding of the house remaining = Total siding - Siding covered

= 2,250 - 2,240

= 10 square feet

1 quart covers 80 feet

Therefore, 1 quart will cover the remaining 10 square feet

A. The minimum cost of the paint needed to complete the job

Total cost = (Price of gallons × Quantity of gallons needed) + (price of quart × Quantity of quart needed)

= (29 × 7) + (18 × 1)

= 203 + 18

= $221

Minimum cost needed = $221

B. How much paint is left over

Recall

1 quart covers 80 square feet

And remaining siding to be covered = 10 square feet

That is,

10/80 = 1/8 of a quart paint used

Remaining quart paint = 1 - 1/8

= 7/8 quart paint