11/9 cubic yard for every 6-inches deep.
You will need about 65.185 cubic yards (83.6 tons) of gravel for this area.
If you use a depth of 3 inches, that area will be about 16.2 cubic yards (around 20.785 tons) of gravel.
You will need about 463 cubic yards (around 594 tons) of gravel for this area.
5.16 yd^3 (when they say a "yard" of gravel, they mean a cubic yard).
486 cubic feet
A rectangle area that is 12 feet by 14 feet by 6 inches deep is equal to 3.11 cubic yards. This job would require 4.2 tons of gravel.
That depends on how deep you want to spread it. On that area, it takes 0.463 cubic yards for every inch deep.
The amount of gravel needed to cover 252 square feet depends on how thick (that is, deep) you want the gravel. If you want the gravel to be 3 inches thick... Convert the measurement to the same units. We'll use feet. 3 inches = 1/4 foot Multiply the thickness times the area to get volume in cubic measure. 1/4 feet x 252 feet = 63 cubic feet Gravel in the US is usually sold by the cubic yard, which is 27 cubic feet Thus, 63/27 = 2 1/3 cubic yards 2 1/3 cubic yards of gravel will cover 252 square feet of area to a dept of 3 inches.
Square feet measure area, and yards measure length. If you mean FEET in 21 yards, the answer is 63 (3 times 21). If you mean square feet in 21 SQUARE YARDS, the answer is 189 (three times three times 21).
You will need 20 cubic yards or 25.7 tons of gravel.
5.55 cubic yards of gravel
nine feet are in three yards.