One 18 inch x 18 inch tile = 1.5 ft x 1.5 ft = 2.25 sq ft.400 sq ft x 1 tile/2.25 sq ft = 177.77 = 178 tiles
6 x 24 inch tile = 144 sq in = 1 sq ft 400/1 = 400 tiles
400 ft x 300 ft = 120,000 sq ft = 2.755 acres (approx)
One gallon covers 400 sq ft on a smooth surface one coat. For rougher surface, much less per gallon, 200-300 sq ft oer coat. One gallon costs between $20-$50 depending on quality.
If you are talking house wise...400 sq is incredibly small...most likely a one floor house. One room probably.
It is not entirely clear what the question is asking but the areas can be configured as80000 sq ft = 400 * 200 sq ft leaving an area of 400 * 200 sq ft, then 40000 sq ft = 400 * 100 sq ft leaving an area of 400 * 100 sq ft, then 10000 sq ft = 100 * 100 sq ft leaving an area of 300 * 100 sq ft, then 5000 sq ft = 100 * 50 sq ft leaving an area of 250 * 100 sq ft.
400 sq ft = 37.161 sq meters (rounded)
1 sq m = 10.76 sq ft, so 400/10.76 = 37.17 sq m
400 (sq feet) = 37.161216 sq meters
400 sq. miles = 27,878,400 sq. ft. x 100 = 2,787,840,000 sq. ft.
16 ft * 25 ft = 16*25 = 400 sq ft.
1 sq. m = 10.7639 sq. ft.so: 400 sq. m. = (400 * 10.7639) 4305.56 sq. ft.
20 ft X 20 ft
400.
I would say a 40,000 BTU furnace could big enough to heat a 400 SQ ft house, but where have you found a 400 SQ Ft house?
really big
15 lb. 400 sq. ft. 30 lb. 200 sq. ft.