# Circles: Circumference & Area

Calculate the circumference and area of circles using the formulae C = πd (or 2πr) and A = πr², and solve problems involving perimeters and areas of composite shapes that include circular parts

Builds on: Angles in triangles (age 11+) (hard, https://ai.page/c/angles-in-triangles-age-11/en.md), Parts of a circle (hard, https://ai.page/c/parts-of-a-circle/en.md)

Concept id: circles-circumference-and-area. Subject: maths. Licence: CC BY-SA 4.0.

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