Find Prism Volume by Packing Practice Test

A student builds a right rectangular prism from unit cubes. The base layer has 6 cubes in each row and 2 rows (so the layer is a 6-by-2 rectangle). The prism has 4 equal layers stacked with no gaps or overlaps. Packing with unit cubes gives the same volume as multiplying the length, width, and height. What is the volume of the prism?

A right rectangular prism is built from unit cubes. The base layer has 2 rows of 10 cubes (20 cubes in one layer). The prism is 5 layers tall, and the layers line up so the prism is completely packed with no gaps or overlaps. This means the volume by packing equals the volume by multiplying the three dimensions. What is the volume of the prism?