The area is the amount of surface a shape covers, measured in square units. A rectangle can be split into rows of unit squares, so the area is the number of rows times the number in each row — length × width. A 6 cm by 4 cm rectangle holds 6 × 4 = 24 square centimetres. Adding the sides gives only 10, and going around the edge gives the perimeter; area always needs a multiplication and covers the whole inside.
Explore this idea with maths tools
Maths you can move
Build 8 + 5
Tap two gold counters to fill the ten-frame.
8 in the frame + 5 waiting. The total stays the same.
Words to know
- area
- the amount of surface a shape covers, in square units
- square centimetre
- a square 1 cm by 1 cm, the unit of area used here
- row
- a line of unit squares across the rectangle
Worked examples
Area of 6 cm by 4 cm
- 1.6 rows of 4 squares.
- 2.6 × 4 = 24 square cm.
= 24
Area of 5 cm by 3 cm
- 1.5 rows of 3 squares.
- 2.5 × 3 = 15 square cm.
= 15
Area of 9 cm by 7 cm
- 1.9 rows of 7 squares.
- 2.9 × 7 = 63 square cm.
= 63
For parents
Method: Draw the rectangle as a grid of 1 cm squares and count them.
What to say: Ask 'how many squares fit inside?' — area is rows times columns, not the sides added.
Common mistakes:
- Adding the sides instead of multiplying.
- Working out the perimeter by mistake.