Circumference of a circle

The Maths Habit

How many times does a bike
wheel turn in one kilometre?

About 450

Radius
From the centre to the edge.
Diameter
All the way across, through the centre.
Circumference
The distance around the outside.

C = π × d

Work out the circumference to 1 decimal place.

C = π × d
C = π × 24 = 75.4 cm
Answer75.4 cm
24 cm24 cm24 cm
C = π × d
C = π × 30 =94.2 cm
Answer94.2 cm
C = π × d
C = π × 24 = 75.4 cm
Answer75.4 cm
24 cm24 cm24 cm
C = π × d
C = π × 17 = 53.4 cm
Answer53.4 cm
C = π × d
C = π × 24 = 75.4 cm
Answer75.4 cm
24 cm24 cm24 cm
C = π × d
C = π × 11 = 34.6 cm
Answer34.6 cm
C = π × d
C = π × 24 = 75.4 cm
Answer75.4 cm
24 cm24 cm24 cm
C = π × d
C = π × 4.6 = 14.5 m
Answer14.5 m
C = π × d
C = π × 24 = 75.4 cm
Answer75.4 cm
24 cm24 cm24 cm
C = π × d
C = π × 85 = 267.0 mm
Answer267.0 mm

Work out the circumference to 1 decimal place.

Circumference and area of a circle worksheet, page 1

Circumference and area of a circle worksheet, page 2

Answer sheet

  1. A bike wheel has a diameter of 70 cm. How many full turns does it make in 1 km?

    454

  2. A circle has a circumference of 50 cm. Work out its diameter to 1 decimal place.

    15.9 cm

  1. Find the circumference to 1 decimal place.

    28.3 cm
    9 cm

  2. Find the circumference to 1 decimal place.

    40.8 m
    6.5 m

  3. The circumference of a circle is 40 cm. Find its diameter to 1 decimal place.

    12.7 cm
Exit tickets to print