How much concrete to fill a 6 inch wide hole by 36 inches deep?

To determine the amount of concrete needed to fill a 6-inch wide hole that is 36 inches deep, first calculate the volume of the hole. The hole is cylindrical, so use the formula for the volume of a cylinder: Volume = πr²h. The radius (r) is half the diameter, which is 3 inches, and the height (h) is 36 inches. Thus, the volume is approximately 3.14 x (3 in)² x (36 in) ≈ 339.29 cubic inches, or about 0.197 cubic feet.