Question

Steve is planning to paint his bathroom. The bathroom measures 8 feet by 9 feet with 8-foot ceilings. The window measures 2 feet by 3 feet, and the door measures 7 feet by 4 feet. Steve plans to buy paint that covers 200 square feet per can. How many cans of paint does Steve need to paint two coats?

Answer 1

The total area of the walls of the bathroom can be calculated by multiplying the perimeter of the floor by the height of the walls, as shown in the following diagram:

The perimeter of the floor (in feet) is:

`P=9+8+9+8=34`

Then, the area of the walls is:

`A=P* h=34*8=272`

We should subtract the area of the window and the door from the total area of the walls. The area of the window is:

`A_W=2*3=6`

And the area of the door is:

`A_D=7*4=28`

Then, the total surface (in square feet) that will be covered by paint is:

`S=272-6-28=238`

Since Steve is going to paint two coats, then the surface area should be covered twice, and the total surface that is going to be painted is:

`2*238=476`

Two cans of paint will be enough to cover 400 square feet, and three cans would be needed to cover up to 600 square feet.

Since the total surface that is going to be painted is 476 square feet, then, Steve needs 3 cans of paint.