Volume by counting unit cubes
The question
cm³
Each small cube is 1 cm³. How many cubes make this solid?
Counting unit cubes
How it works.
2 along×2 back=4
one layer=4 cubes
4×5 layers=20
2 × 2 × 5=20 cubic cm
- 01
Start with one layer — the cubes lying flat on the bottom. There are 2 along the front and 2 going back.
- 02
So one layer is 4 cubes.
- 03
Now count the layers stacked up: there are 5. Each one holds the same 4 cubes, so multiply.
- 04
That is 2 × 2 × 5 — the three directions of the block. The volume is 20 cubic cm.