You are painting your two car garage, including the door. The walls measure 12 feet by 12 feet, with a 10-foot ceiling. How many gallons of paint will you buy if it covers 400 square feet per gallon?

1.2 gallons

Step-by-step explanation:

We assume that each room is rectangular with four walls and no doors. If the dimensions are length l, by width w with height h, then there are two walls with area l*h and two walls with w*h.

The total area of the room is thus: 2lh + 2wh = 2h (l+w).

l = 12ft, w = 12ft, h = 10ft (all given)

Area of walls = 2h (l+w) = 2*10 (12+12)

Area = 2*10*24 = 480 square feet

Each gallon of paint covers 400 square feet. So, you will need to buy

480 / 400 = 1.2 gallons

You will need to buy 2 gallons