91 with .79 cubic inches to spare.
729 of them!
As the question is presented the answer must be none. A box cannot have a volume of 729 inches because volumes are measured in cubic inches, not inches. If you ignore that, the answer is a maximum of 729. However, it could be as low as none! If the box had dimensions of 0.5 in*2 in*729 in, it would have a volume of 729 cubic inches but not a single 1 inch box would fit in.
8^3 = 512
It depends on two things: It depends on the units of measurement used for the boxes which you have chosen not to give. If each box is 14 ft x 21 ft x 10 ft then none will fit. Second, it depends on the dimensions of the cubic yard. If the boxes are 14 inches x 21 inches x 10 inches, and the cubic yard measures 9 inches x 9 inches x 21.33... inches not a single box will fit. The cubic yard is simply too long and narrow.
Slightly larger than one cubic foot. It is the amount of corn that will fit into a box about 15 inches long, 12 inches wide and 12 inches deep. (2,150 cubic inches)
5 inches times 6 inches times 9 inches are 270 cubic inches. 270 cubic inches are 4.42450728 cubic decimeters. 1 cubic decimeter is 1 liter. 4.42450728 cubic decimeters are 4.42450728 liters.
A box that big is 6912 cubic inches, filled with osmium(the densest element) it would be very heavy, about 5600 lbs.
500
A 5-gallon bucket measures approximately 11.9 inches in diameter and 15.9 inches in height. A cubic yard box that is 36x36x36 inches can fit approximately 11 buckets (3x3 base layer with 1 bucket in the center and 2 additional layers on top).
The 3 foot square box contains 46,656 cubic inches. The 3 inch square cube has 27 cubic inches. The division of 46,656 by 27 yields 1728 3x3x3 cubes inside the larger one.
12