Area of rectangles for 11 plus
21 October 2026
Understanding area questions
Area questions often appear in the 11 plus Maths exam. Children are expected to know how to calculate the area of rectangles using the correct formula and units.
The formula for area
To find the area of a rectangle, multiply the length by the width. Both measurements must be in the same unit, such as centimetres (cm) or metres (m).
Checking units before you start
Always check that both the length and width are given in the same unit. If not, convert one so that both match before you calculate the area.
Worked example
Suppose a rectangle has a length of 5 cm and a width of 4 cm.
First, multiply the length by the width: 5 cm × 4 cm = 20 cm².
The correct answer is 20 cm².
Writing the answer clearly
Make sure your child includes the correct unit in their answer. For area, this means writing square centimetres (cm²) or square metres (m²) as needed.
Key insight: Practise a variety of area questions together, using different numbers and units. This helps children become confident with both the calculation and the units, and spot any unit conversions needed before they start.
