A box is not a standard unit: different boxes have different sizes and so can accommodate different numbers of cubic inches.
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