Circumference of a circle
You learn to work out the circumference of a circle.
How to work it out
- Multiply radius by 2 for diameter.
- Multiply diameter by π (approximately 3.14).
A circle has radius 5 cm. What is the circumference?
- The diameter is 2 × 5 = 10 cm.
- The circumference is 10 × 3.14 ≈ 31.4 cm.
Another example
A circle has diameter 8 m. What is the circumference?
Circumference is diameter × π: 8 × 3.14 ≈ 25.12 m.