Find out how many square feet you need, and multiply that number by four.
For example: If your room measured 10 feet by 10 feet, you need 100 square feet. For 6 inch tile, multiply that by four and you find you'll need 400 tile.
236 18-inch tiles.
5,184 2-square-inch tiles are needed.
128.2 tiles
400 6" x 6" tiles are needed.
22.2 tiles so buy 23 tiles.
It would be 9 tiles wide by 12 tiles long. That gives you a total of 108 tiles.
35
54
247.1
You will need 44 six inch tiles to cover 11 square feet.
I hope you meant 20 inch by 20 inch tiles, but the answer is around 13.38
720 4"x 8" tiles are needed.