Mathematics · Grades 8–12
Volume of a cone
Use the perpendicular height and radius, not the diameter.
The key idea
Use the perpendicular height and radius, not the diameter.
V = πr²h/3
Worked examples
A cone has radius 2 cm and height 90 cm. Use π = 3.14. Find its volume in cm³.
3.14 × 2² × 90 ÷ 3 = 376.8
376.8 cm³
A cone has radius 7 cm and height 60 cm. Use π = 3.14. Find its volume in cm³.
3.14 × 7² × 60 ÷ 3 = 3077.2
3077.2 cm³
Try it yourself
A cone has radius 10 cm and height 78 cm. Use π = 3.14. Find its volume in cm³.
A cone has radius 10 cm and height 6 cm. Use π = 3.14. Find its volume in cm³.
Check your understanding
Answers and marking notes
- 8164 cm³
3.14 × 10² × 78 ÷ 3 = 8164
- 628 cm³
3.14 × 10² × 6 ÷ 3 = 628
Further reading and review references
These are reference links, not copied exercises, institutional endorsement or proof of independent review.
Learning preview · teacher review required. Grade bands are approximate, not official curriculum alignment.