Answer:

Explanation:
There are three different box sizes: The small, the medium, and the large size.
The small box has half the volume of the medium box. If x is the volume of the medium box, then:
The volume of small box =

The large's volume is twice the medium's volume, thus:
The volume of large box=2x
The total volume of the three boxes is:

Operating:

The expression for the combined volume of the three boxes is
