Finding the area of L-shapes and compound rectilinear shapes by splitting into rectangles and adding the areas.
Where your child meets this in real life: Calculating floor tiles needed for an L-shaped kitchen or grass seed for an irregular lawn
This topic isn't tested on its own, but it sits inside questions on tested topics. Each SEAG paper has 28 maths questions. Questions 29 to 50 are multiple choice with five possible answers, and questions 51 to 56 need a short written answer. With 56 questions in 60 minutes across English and maths, that is about a minute per question.
SEAGReady breaks area of compound shapes into 3 steps, taught in order so each skill builds on the last.
Split an L-shape into two rectangles and add their areas when all necessary dimensions are labelled
Calculate unlabelled dimensions from given measurements before finding the total area
Find compound shape area by calculating a large enclosing rectangle and subtracting the cut-out section
Try three free questions from our area of compound shapes course. They start easy and get harder, so you can see where your child's confidence runs out. If they manage the last one without a hint, this topic is probably secure. If not, the steps above show where to start.
The diagram shows Millie's L-shaped living room split into two rectangles. What is the total floor area?
The diagram shows Aaron's L-shaped bathroom floor. Work out the missing lengths, then find the total floor area.
The diagram shows a rectangular public lawn. The two shaded regions are identical flower beds. What area of lawn remains?
This is the exact interactive worked example your child sees in SEAGReady. Step through it and watch the method build up.
Charlotte's bedroom is an L-shape. She wants to buy carpet for the floor. The room is made of two rectangular sections: one is 4 m by 3 m and the other is 5 m by 2 m.
What is the total floor area of the bedroom?
(4 × 3) + (5 × 2)
First rectangle: 4 m by 3 m
4 × 3 = 12 m²
Step 1 of 3
Charlotte's bedroom is an L-shape. She wants to buy carpet for the floor. The room is made of two rectangular sections: one is 4 m by 3 m and the other is 5 m by 2 m.
What is the total floor area of the bedroom?
The total floor area is 22 m².
The key insight: Split any compound shape into rectangles, find each area, then add them up!
Common mix-up: 4 × 3 × 5 × 2 = 120 m². Multiplying all dimensions together is incorrect - calculate each rectangle separately, then add.
These are the misconceptions we see most often in area of compound shapes, including the ones our practice questions are specifically designed to catch.
Struggling with area of compound shapes? The real gap is often in one of these earlier topics.
Sitting the SEAG test this November? Read our last-month revision plan, Paper 1 vs Paper 2 and test day guide.
SEAGReady finds the exact step where your child gets stuck, teaches it with worked examples like the one above, and brings it back for review so it sticks.
Free to start · no card needed