Question

A room measures 10m long 6m wide and 4.5m high. The area occupied by windows and doors is 15m squared. The walls were covered with a wallpaper completely.
A) calculate the area of the wallpaper used to cover the walls
B) the floor was covered using square tiles of length 20cm .How many boxes of tiles will be needed if one box holds 10 tiles?

Answer 1

A) The total area of the walls can be calculated by finding the total surface area of the room (excluding the windows and doors) and then subtracting the area of the windows and doors.

Total surface area = 2(height x length) + 2(height x width) + 2(length x width)
Total surface area = 2(4.5 x 10) + 2(4.5 x 6) + 2(10 x 6)
Total surface area = 2(45) + 2(27) + 2(60)
Total surface area = 90 + 54 + 120
Total surface area = 264 square meters

Area occupied by windows and doors = 15 square meters

Area of wallpaper used to cover the walls = Total surface area - Area of windows and doors
Area of wallpaper used = 264 - 15
Area of wallpaper used = 249 square meters

Therefore, 249 square meters of wallpaper will be needed to cover the walls.

B) The total area of the floor is the same as the length x width of the room.

Total area of the floor = length x width
Total area of the floor = 10 x 6
Total area of the floor = 60 square meters

Each tile covers 0.2 x 0.2 = 0.04 square meters.

Number of tiles needed = Total area of the floor / Area covered by one tile
Number of tiles needed = 60 / 0.04
Number of tiles needed = 1500 tiles

Since one box holds 10 tiles, the number of boxes needed = 1500 / 10 = 150 boxes

Therefore, 150 boxes of tiles will be needed.