78.63 square feet
You will need approximately 23.4 tiles, so 24 tiles. Assuming 13x13 tiles is in inches.
41
A 13 x 13 tile is 1.74 sq ft. 144/1.74 = 123 tiles
23 tiles if you want to add for waste it would be 26.
These 327 tiles will cover an area of 383.8 square feet.
It depends on whether the tiles are 13 ft x 13 ft, 13 inch x 13 inch, 13 cm x 13 cm etc.
13'x13' = 169 square feet
It depends on the size of the tiles and also, to some extent, on the shape of the area that you need to cover.
The number of 13 inch tiles needed will depend on the actual dimensions of the floor rather than the square footage. If the room is square, 169 tiles, with 1/16 inch or larger grouted seams, will completely cover it. If the floor is rectangular, additional tiles will be needed, the exact number depending on how many tiles must be cut. As a general rule, approximately 10 percent extra is usually sufficient to cover waste from cutting and accidental breakage.
13 feet by 12 feet is the same as 156 inches by 144 inches. Multiply 156 by 144 to find that the room's area is 22464 square inches. Next, find the area of each tile by multiplying 13 by 13 to get 169 square inches. We need to find how many 169 square inch tiles can fit in a 22464 square inch room, so divide 22464 by 169 and get 132.923077. Round that up to the nearest whole number and get:133 tiles.
300 mm = 0.300 meters and 450 mm = 0.450 meters. Therefore, the area of each tile in square meters is 0.300 X 0.450 = 0.135 square meters. Therefore, the smallest number of tiles that can cover an area of 13 square meters is 13/0.135 or at least 97 tiles.
13 x 13 (assumed inches) is 13/12 feet x 13/12 feet, so the area of one tile is 169/144 square feet. To cover 100 square feet you need (100)/(169/144) tiles which works out to (100 x 144)/169 = 14400/169 = 85.2, make it 86 tiles