You have an empty box which is a 11cm cube. You also have a supply of blocks. You have 54 2cm cubes, 24 3cm cubes and two 5cm cubes. Pack all 80 cubes into the box.
well, its not impossible at least. The total area of the cubes you need to put in is 1330 cc, while the huge box is 1331 cc. That means that there while be a 1cm cube extra space in there.