Answer:
A) The number of wallpapers needed to cover the walls is 6 double roll wall papers
B) The number of wall paper border rolls needed is 3 rolls
Explanation:
A) The given parameters are;
The dimensions of the room are 9 ft. by 12 ft. by 8 ft. high,
The area one double role wallpaper covers = 60 ft.²
Therefore, we have;
The area of the room wall = 12 × 8 × 2 + 9 × 8 × 2 = 336 ft²
The number of double rolls of wallpaper to be used = Area of wall/(area of wallpaper) = 336/60 = 5.6
Therefore, given that the wall papers are sold in single units, we round up to the next whole number of units to get;
The number of wallpapers needed to cover the walls = 6 double roll wall papers
B) The borders of a wallpaper are installed parallel (and installed along) to the ceiling line
Therefore, the amount of wallpaper border required is given as follows;
Wall paper border length required = 2 × Length of the room + 2 × Width of the room
∴ Wall paper border length required = 2 × 9 ft. + 2 × 12 ft. = 42 ft.
The size of each wall paper border sold = 5 yd. = 15 ft.
Therefore;
The number of wall paper border rolls required = 42 ft./(5 yd.) = 42 ft./(15 ft.) = 2.8 rolls
Therefore, we round up to get the number of wall paper border rolls needed as 3 rolls of wall paper borders.