A foot is a unit of length. A square foot is a unit of area. The two units are therefore incompatible.
$136.80 plus tax
80" * 57" = 4560 sq inches = 4560/(12*12) = 31.66.. sq ft
5220.5 sq ft
19681.81 sq ft
1076.391042 sq. ft.
32 sq. ft.
1 sq yd are in 9 sq ft
3 sq yards = 3*9 sq ft = 27 sq ft
5468 sq ft
55,000 sq ft.
3100 of them.
1120 sq ft