How to explain perimeter in perimeter to your child: Example question
31 October 2026
Understanding perimeter is a key part of primary maths. Children often find it easier when they see a clear example with simple shapes and measurements. Here is a step-by-step question to help your child see exactly how to add up the sides of a rectangle.
Example question
Find the perimeter of a rectangle with length 9 cm and width 6 cm.
Step 1
Draw a rectangle. Label one side 9 cm and the next side 6 cm.
Step 2
Remember: a rectangle has two sides of each length. So the sides are 9 cm, 6 cm, 9 cm, 6 cm.
Step 3
Add all the side lengths together: 9 + 6 + 9 + 6 = 30
Step 4
Write the answer with units: The perimeter is 30 cm.
After seeing this example, your child should recognise that finding the perimeter means adding all the sides together. The same method works for any rectangle or shape with labelled sides. Now your child can try similar perimeter questions with confidence.
