There is no sensible answer to this question. A gallon is a measure of volume and and that cannot be converted to a measure of area.
18 x 18 = 324 square feet
18 square meters is the same as 193.75 square feet.
There are: 8 times 18 = 144 square feet
18 square feet = 1.67 square meters.
18 square feet is about 1.7 (1.67225) square meters.
There are 144 18 square inch tiles in an area of 18 square feet.
2.25 square feet.
There are: 18*15.5 = 279 square feet
The answer is NONE!!!! Because 'Gallons' is a measure of liquid volume , and 'Square Feet' is a measure of area.
18 US gallons equates to 2.4 (2.40625) cubic feet.
10' x 18' = 180 square feet.
18 x 12 = 216 square feet.