The radius of a circle is the distance between the centre of a circle and the edge. The diameter of a circle is the distance between two edges of a circle passing through the centre. The diameter is double the size of the radius.

The circumference of a circle can be calculated using the following formula: C = 2πr, where r is the radius of a circle.

The area of a circle is given by the formula: A = πr², where r is the radius of the circle.

1

Calculate the area of a circle with radius 5 cm.

2

Given that r = 8 cm, calculate the circumference of the given circle.

3

Sketch a diagram of a circle, labelling for its radius and diameter.

4

Given that the radius of a circle is 4 cm, calculate the length of its diameter.

5

Use the given diagram to calculate the diameter of the circle.