Question 231445
You have:


height = 15 cm.
width = 10 cm.
depth = 18 cm.


Take 4 cm cubes and lay them in the bottom of the box.


You get 2 cubes wide by 4 cubes deep by 1 cube high.


You do this with 8 cubes.


Lay another layer.


that's another 8 cubes.


Lay another layer.


That's another 8 cubes.


All together you havre 24 cubes in the container.


That's 3 cubes * 2 cubes * 4 cubes = 24 cubes.


You can't put anymore in because 15 inch cube height / 4 = 3 plus a fraction, and 10 / 4 = 2 plus a fraction, and 18 / 4 = 4 plus a fraction, and fractions are not allowed.


Total square cm you have used is 12 * 8 * 16 = 1536.


Total square cm in the container is 15 * 10 * 18 = 2700.


The difference is empty space.