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.
There are 9 square yards in a cubic yard at a thickness of 3 inches. This is because there are 9 square feet in a square yard and 36 cubic feet in a cubic yard, so the area is 9 square yards if the thickness is 3 inches.
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.
One cubic yard covers 81 square feet 4 inches thick.
1 yard topsoil covers 100 square feet to 3 inches, 200 square feet to 1.5 inches and 300 square feet to 1 inch.
5inches
1 cubic yard/(1/9 of a yard) = 9 square yards.
You have given three dimensions; square feet has only two dimensions. Do you mean cubic feet?
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.