The perimeter of tile which is 3 by 3 would be 12. If each side is 3 and the tile is a square which has four sides we can do 3 x 4 to determine the perimeter of the tile. To determine perimeter just add up all the sides. In this case since it’s a square you are able to multiply. 3 x 4 or 3 + 3 + 3 + 3 = 12