This activity is about finding the areas of circles, given their diameters.
You need to learn this important formula for a circle of radius, r :
Area of a circle = π r2
Remember that the radius is half the diameter.
Example
Find the area of a circle of diameter 12 cm.
Answer
First, work out the radius, which will be 12 ÷ 2 = 6 cm
Area = π r2 = π x 62 = π x 36 = 113.1 cm2 (1 dp)
Let's have a go at some questions now.
View the activity introduction for more information on the topic
Read the question aloud
Open the accessibility toolbar to change fonts and contrast, choose a different language, use a ruler and more
Question
Do you want to skip questions and finish?
Hold up, it looks like there may be an issue with your spelling. Why not try it again?
You need to check your answer before you proceed. Are you sure you want to skip?
Teacher explanation