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Kathryn has been offered a job to paint the outside of a barn. If one gallon costs $40 and covers 400 square feet. How much will it cost to paint the barn with one coat?

User Seder
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1 Answer

8 votes

Answer:

The answer is below

Explanation:

The question is not complete but I would solve a similar question:

Alexis needs to paint the four exterior walls of a large rectangular barn. The length of the barn is 80 feet, the width is 50 feet, and the height is 30 feet. The paint costs $28 per gallon, and each gallon covers 420 square feet. How much will it cost Alexis to paint the barn? Explain your work.

Solution:

The barn has four walls. Let the four walls be labeled as w, x, y and z.

The area of wall w = 80 feet * 30 feet = 2400 feet²

The area of wall x = 50 feet * 30 feet = 1500 feet²

The area of wall y = 80 feet * 30 feet = 2400 feet²

The area of wall z = 50 feet * 30 feet = 1500 feet²

The total area of the four walls = area of wall w + area of wall x + area of wall y + area of wall z

The total area of the four walls = 2400 + 1500 + 2400 + 1500 = 7800 ft²

Given that each gallon of paint can cover 420 feet². Therefore number of gallon needed is:

number of gallon needed = 7800 ft² ÷ 420 ft² per gallon = 18.57

Since the gallon must be a whole number and 18 gallons wont be enough, therefore number of gallon needed is 19 gallons.

Cost of painting = 19 gallons * $28 per gallon = $532

User Ahmad Alkhatib
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