How it works
Cut a shape into rectangles. Find each area. Add the areas.
A rectangle 4 by 8 can be cut into 4 by 2 and 4 by 6.
The two parts add to the whole.
Worked examples
Two parts
- A rectangle is 4 rows of 8. Cut it after 2 columns.
- The left part is 4 × 2 = 8. The right part is 4 × 6 = 24.
- 8 + 24 = 32, and 4 × 8 = 32.
A missing part
- 2 times 5 is 2 times 2 plus what?
- 2 × 5 = 10 and 2 × 2 = 4.
- 10 − 4 = 6, so it is 2 times 3, which is 6.
An L shape
- Cut an L shape into two rectangles, 3 by 8 and 2 by 4.
- 3 × 8 = 24 and 2 × 4 = 8.
- 24 + 8 = 32 square units.
A taste of the worksheet
These are the first problems of set A. The printable sheet has many more, with an answer key.
- A placemat is cut in two parts. How many squares are in the left part? ___
- How many squares are in the whole placemat? ___
- Which sentence matches the cut?
- 5 × 7 = 5 × 5 + 5 × ___
- A card has 4 rows of 8 squares. Cut it so 3 columns stay. How many columns come off? ___