← 2.6 Area of a Part of a Circle
Area of an annulus
Mathematics · Grade 10 · about 40 minutes
The ring between two concentric circles has area pi times (R squared minus r squared).
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- 8 sections of explanation, worked examples and diagrams
- 1 practice task with hints and worked answers
- A quiz that marks itself as you go
- Your progress kept across every subject you take
Other lessons in this sub-strand
- Arcs and sectors
- Segments and applications
- Area of an annulus
- Finding a missing radius of an annulus
- Minor and major sectors
- Perimeter of a sector
- Finding the angle or radius of a sector
- Area of an annular sector
- The chord and the isosceles triangle
- Minor and major segments in depth
- Common region of two intersecting circles
- Gardens, tracks, dartboards and paths