You have decided to wallpaper your rectangular bedroom. The dimensions are 12 feet 6 inches by 10 feet 6 inches by 8 feet 0 inches high. The room has two windows, each 4 feet by 3 feet and a door 7 feet by 3 feet. Determine how many rolls of wallpaper are needed to cover the walls, allowing 10% for waste and matching. Each roll of wallpaper is 30 inches wide and 30 feet long. How many rolls of wallpaper should be purchased?

First calculate how much wallpaper is needed:

add: 2 walls of 12.5 ft length x 8 ft high = 200 ft²

add: 2 walls of 10.5 ft length x 8 ft high = 168 ft²

subtract: 2 windows of 4 ft length x 3 ft high = 24 ft²

subtract: 1 door of 3 ft length x 7 ft high = 21 ft²

Wallpaper needed: 200 + 168 - 24 - 21 = 323 ft²

Add 10% for waste and matching: 323 + 323 (10%) = 355.3 ft²

Next, calculate the amount of wallpaper in one roll:

0.5 ft wide x 30 ft length = 15 ft²

Lastly, calculate how many rolls are needed:

355.3 : 15 = 23.7

Since you can only purchase an entire roll (and not a fraction of it),

round the answer up to the nearest whole roll.

Anser: 24 rolls of wallpaper should be purchased.