If you're talking floor tiles as opposed to wall tiles and by 12x12 you mean they are 12 inches square, then the answer is 300. Because each tile is one square foot and a 15'x20' room is 300 square feet. Simple, eh?
80 if the tiles are 12x12 - 12x12 is one square foot covering 80 you would need 80 tiles
To determine how many 12x12 tiles you need for 60 square feet, first calculate the area of one tile. A 12x12 tile covers 1 square foot (12 inches = 1 foot). Therefore, for 60 square feet, you will need 60 tiles.
375
30 but get 4 extra in case you break some
To calculate the number of 18x18 ceramic tiles needed for a 12x12 room, first determine the area of the room and the area of one tile. The area of the room is 144 square feet (12x12), and the area of one tile is 2.25 square feet (1.5x1.5). Dividing the room area by the tile area, you'll need about 64 tiles (144 ÷ 2.25). It's advisable to purchase a few extra tiles to account for cuts and breakage.
forty
80 if the tiles are 12x12 - 12x12 is one square foot covering 80 you would need 80 tiles
256 tiles
The tile is bigger than the area that you want to cover (12x12 > 10x11) so one tile will do. <><><><><> However, if you meant 12x12 INCH tiles, and a 10x11 FOOT room, you would need 110 tiles.
13 boxes with 13 tiles in each
To determine how many 12x12 tiles you need for 60 square feet, first calculate the area of one tile. A 12x12 tile covers 1 square foot (12 inches = 1 foot). Therefore, for 60 square feet, you will need 60 tiles.
144
585
168
650
549!
375