Circles & Volume
π links a circle's width to everything else about it.
CircumferenceArea of a circleVolume of prisms & cylindersSurface area
📖 Learn
Circumference
C = πd (or 2πr).
Area
A = πr². Square the radius first!
Prisms
Volume = area of cross-section × length. Cylinder: πr²h.
Worked example
Area of a circle, radius 5 cm (1 d.p.)
- 1A = π × 5²
- 2= π × 25
- 3≈ 78.5 cm² ✅
⭐ Practise
π
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