Similar Shapes

This lesson can be used for revision for the higher Maths GCSE. The examples are quick and concise with exam style questions, go to GCSE Maths if you need more in-depth explanations.

What does similar mean in maths?
Two shapes are similar if one is the enlargement of another.

You may be asked to find missing lengths, areas and volumes. You may also be asked to solve word problems involving similar shapes.

Example 1: The following shapes are mathematically similar
a) Calculate the length of BC.
b) Calculate the length of EF.
c) If the area of the big shape is 320 cm² what is the area of the similar shape.
d) If the volume of the small shape is 500 cm³ what is the volume of the bigger shape.

Example 2:
Prism P has triangle ABC as its cross section.
Prism Q has triangle DEF as its cross section.
AC = 6 cm
DF = 12 cm
The area of the cross section of prism P is 10 cm².
The length of prism P is 15 cm.
Work out the volume of prism Q. Go to next lesson