11+ Maths · Topic explained
Area
How many tiles do you need to cover a floor?
The big idea
Area is how much flat space a shape covers, counted in squares.
Picture it
Like tiling a floor: rows of squares. 3 rows of 5 = 15 squares.
Key words
- area
- The space inside a flat shape.
- square centimetre (cm²)
- A square 1 cm by 1 cm: the unit we count.
- rectangle rule
- Area = length × width.
- triangle rule
- Area = ½ × base × height.
Worked examples
- 1Warm-up
Find the area of a rectangle 7 cm by 4 cm.
- Area = length × width
- 7 × 4 = 28 cm²
- 211+ standard
A triangle has a base of 10 cm and a height of 6 cm. Find its area.
- The rectangle around it: 10 × 6 = 60
- The triangle is half of it
- 60 ÷ 2 = 30 cm²
- 311+ standard
Find the area of this L-shape.
- Split it into two rectangles
- 10 × 4 = 40 and 6 × 4 = 24
- 40 + 24 = 64 cm²
- 411+ standard
A square has an area of 49 cm². What is its perimeter?
- Which number times itself is 49? 7
- Each side is 7 cm
- Perimeter = 4 × 7 = 28 cm
The common mistake
The mistake
Triangle area = base × height = 10 × 6 = 60 cm².
Instead
Halve it: ½ × 10 × 6 = 30 cm².
Why: A triangle is exactly half of the rectangle drawn around it.
Where it comes up in the 11+
Rectangles, triangles, L-shapes split into rectangles, and area and perimeter together.
The video
Video coming soon
We're making a short video that explains area step by step. Until then, everything it covers is on this page.
Free printable
Area worksheet
Practice questions on this topic to print and try on paper, at home or on the way to school.
Download the worksheet (PDF)Free account needed: it takes a minute.
Quick quiz
Have a go first, then tap to see the answer.
1. What is the area of a square with sides of 6 cm?
- 24 cm²
- 36 cm²
- 12 cm²
- 36 cm
Show the answerHide the answer
36 cm²
6 × 6 = 36, measured in square centimetres.
2. A triangle has a base of 8 cm and a height of 5 cm. What is its area?
- 40 cm²
- 20 cm²
- 13 cm²
- 26 cm²
Show the answerHide the answer
20 cm²
½ × 8 × 5 = 20.
3. A rectangle has an area of 48 cm² and a width of 6 cm. How long is it?
- 8 cm
- 42 cm
- 12 cm
- 7 cm
Show the answerHide the answer
8 cm
48 ÷ 6 = 8.