The figure below shows a rectangular prism and a cube:
A rectangular prism and a cube are drawn side by side. The length of the rectangle prism is 5 inches, the width is 4 over 5 inch, and its height is 1 and 3 over 5 inches. The cube has a side length of 1 over 5 inch.
How many such cubes are required to completely pack the prism without any gap or overlap?
