Mrs. Jefferson would like to wallpaper a wall in her guest room. She would like to wallpaper everything but the door. Each roll of wallpaper covers approximately 160 square ft and is 19.85 per roll. How much should Mrs. Jefferson plan to spend on wallpaper? The room is 18ft in length and 12ft in width The door is 7ft in width and 3 ft and length

She would like to wallpaper everything but the door. It means that the area to be covered by the wallpaper would be the area of the 4 walls of the room - the area of the door.

The room is 18ft in length and 12ft in width. Thea area of each side of the room is

18 × 12 = 216 square feet

Area of the 4 sides of the room is

216 × 4 = 864 square feet

The door is 7ft in width and 3 ft in length. Area of door is

7 × 3 = 21 square feet

Area to be covered is

864 - 21 = 843 square feet

Each roll of wallpaper covers approximately 160 square ft. Therefore, the number of rolls needed is

843/160 = 5.26

Since the rolls cannot be a fraction, then she needs 6 rolls

Since a roll costs 19.85, the cost of 6 rolls is

19.85 × 6 = 119.1