This deep dive covers Method: Finding Circumference within Circumference & Area of Circles for GCSE Mathematics. Revise Circumference & Area of Circles in Geometry & Measures for GCSE Mathematics with 11 exam-style questions and 7 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 4 of 10 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Method: Finding Circumference
- Identify if you have radius or diameter
- Use the formula: C = πd (or C = 2πr if you have radius)
- Substitute and calculate
- Include units (same as input: cm, m, etc.)
Practice questions for Circumference & Area of Circles
A circle has radius r. Which pair of formulas gives the correct circumference C and area A?
Explain why the circumference of a circle is measured in cm (or other length units) but the area is measured in cm² (square units).
Quick recall flashcards
Area of Circle
A = πr²
Circumference
C = πd or C = 2πr