11+ Maths: Area of Compound Shapes (CEM & GL)
19 October 2026
Why compound shapes matter
Understanding the area of compound shapes is a key skill for the 11+ CEM and GL exams. These questions regularly appear, testing whether children can break a complex figure into manageable parts. The ability to spot familiar rectangles, squares, triangles, or other shapes within a larger figure helps children approach these problems calmly and logically.
Breaking down the question
Most compound shape questions require children to split the shape into smaller, known shapes. Encourage your child to draw lines on the diagram to separate it into rectangles, triangles, or other simple forms. Once divided, they can use the area formulas they already know, then add or subtract as needed to find the total area.
Finding missing lengths
A common challenge is that not all side lengths are given. Children may need to use subtraction or simple algebra to work out missing sides before calculating the area. Remind your child to check carefully which lengths are known and which need to be found, and to label all sides clearly on their diagram.
Key insight: Focus on method, not just answers
The 11+ exam is not only about getting the correct answer, but also about showing clear working and logical steps. Practising with a variety of compound shapes helps children become confident in their approach. Encourage your child to write out their working and check each part as they go.
Practical applications
Area questions can involve real-life scenarios, such as working out how many tiles are needed to cover a floor or how much paint is required for a wall. Help your child see the link between maths problems and everyday situations. This can make the topic feel more relevant and less intimidating.
