Slightly less than 26 cu. yards.
A cubic yard is 46,656 cubic inches. Spread to a thicknes of 5 inches, a cubic yard of concrete covers 9332.1 square inches, which is 64.8 square feet.
81
One cubic yard covers 81 square feet 4 inches thick.
1 cubic yard/(1/9 of a yard) = 9 square yards.
Apples and oranges. Without knowing how thick the 450 sq. ft. area is or how thick you want it to be you can't convert to cubic yards. A cubic yard has 27 cubic feet. One square foot 3 inches thick would be 1/4 cubic feet. 4 sq. ft. 3 inches thick would be 1 cubic foot. 450 sq. ft. 3 inches thick is 112 1/2 cubic feet or just a bit over 4 cubic yards. 450 sq. ft. 4 inches thick is 150 cubic feet or 5 1/2 cubic yards.
One "yard" of dirt (meaning one cubic yard) contains 46,656 cubic inches. Spread 8 inches thick this will cover 5832 square inches or 40.5 square feet.
A cubic yard is 46,656 cubic inches. Spread to a thicknes of 5 inches, a cubic yard of concrete covers 9332.1 square inches, which is 64.8 square feet.
81
A 9x9 foot slab 4 inches thick requires a minimum of 1 cubic yard. If you go to 6 inches thick you will need 1.5 cubic yards.
1 yard = 36 inches, so 3 inches thick will be 1/12 yard thick. So the area covered will be 12 square yards.
1 yard topsoil covers 100 square feet to 3 inches, 200 square feet to 1.5 inches and 300 square feet to 1 inch.
One cubic yard covers 81 square feet 4 inches thick.
5inches
You have given three dimensions; square feet has only two dimensions. Do you mean cubic feet?
1 cubic yard/(1/9 of a yard) = 9 square yards.
Apples and oranges. Without knowing how thick the 450 sq. ft. area is or how thick you want it to be you can't convert to cubic yards. A cubic yard has 27 cubic feet. One square foot 3 inches thick would be 1/4 cubic feet. 4 sq. ft. 3 inches thick would be 1 cubic foot. 450 sq. ft. 3 inches thick is 112 1/2 cubic feet or just a bit over 4 cubic yards. 450 sq. ft. 4 inches thick is 150 cubic feet or 5 1/2 cubic yards.
1 cubic yard = 3*3*3 = 27 cubic feet = 27 square feet * 1 ft = 27 sq ft * (3*4 inches) = 27*3 sq ft* 4 in = 81 sq ft at 4 inches thick.