Answer:
36 cubes
Explanation:
Volume of the box = 40 x 35 x 30 = 42,000 cm³
Volume of one cube = 10 x 10 x 10 = 1,000 cm³
4 cubes will fit across the length, 3 cubes along the height, and 3 cubes along the width. The width is 35 cm, so only 3 cubes will fit along the width. It doesn't say you can cut cubes in half.
Largest number of cubes that will fit in the box:
(4 x 3 x 3)(1000 cm³/cube) = 36,000 cm³
The entire box can not be filled with cubes. The most that will fit will be
4 x 3 x 3 = 36 cubes