288
You'll need 200 18-inch tiles.
30 tiles! But you'll need more than 30 tiles to cover wastage, breakage, etc.
71 and 1/2 Get 80 to be safe.
To cover 720 sq feet of floor with 18" x 18" tile, you would need 320 tiles.
288
12...
144/2.25=64. 18x18 tile cover 2.25 sq ft area.
You'll need 200 18-inch tiles.
94 (93.33)
Depends on how many are in each box?
30 tiles! But you'll need more than 30 tiles to cover wastage, breakage, etc.
71 and 1/2 Get 80 to be safe.
To cover 720 sq feet of floor with 18" x 18" tile, you would need 320 tiles.
18" x 18" = 1.5' x 1.5' = 2.25 square feet90/2.25 = 40 tiles.
The answer will depend on the units used for measuring the tiles which you have failed to specify.
144/(1.5*1.5) = 64 tiles, but if you are using this to determine how many are needed to tile a room, you need to add at least 10% for edging around the room. So, you probably need at least 71 or more tiles.