Area and Volume: Important Formulas
Mathematics • Grade 10 • Area and VolumeQuick memory: Pyramid and cone volumes are ⅓ of the prism or cylinder with the same base and height.
1. Square Based Pyramid
- Slant heightl² = h² + (a/2)²
- Edgee² = l² + (a/2)²
- Lateral surface areaLSA = 2al
- Total surface areaTSA = a² + 2al
- VolumeV = ⅓ a²h
2. Cone
- Slant heightl² = h² + r²
- Curved surface areaCSA = πrl
- Total surface areaTSA = πr² + πrl = πr(r + l)
- VolumeV = ⅓ πr²h
- Circumference of base = 2πr | Base area = πr²
3. Combined Solids
| Solid | TSA | Volume |
|---|---|---|
| Cylinder + Cone | πr² + 2πrh₁ + πrl | πr²(h₁ + ⅓h₂) |
| Cone + Hemisphere | πr(l + 2r) | ⅓πr²(h + 2r) |
| Cylinder + Hemisphere | 2πrh + 3πr² | πr²(h + ⅔r) |
| Cone + Cone | πr(l₁ + l₂) | ⅓πr²(h₁ + h₂) |
| Prism + Pyramid | a² + 4ah₁ + 2al | a²(h₁ + ⅓h₂) |
4. Cost Estimation and Units
- Quadrilateral areaA = ½ × d × (p₁ + p₂)
- 4 walls + ceilingA = 2h(l + b) + lb
- CostTotal cost = Area × Rate
- 1 m³ = 1000 litres | 1 ft³ = 28.317 litres | π = 22/7
| Quick triples (h, half-base or r, l) |
|---|
| 3, 4, 5 | 5, 12, 13 | 6, 8, 10 | 7, 24, 25 | 8, 15, 17 | 9, 12, 15 |
Exam tips: (1) Find l first. (2) Tents and pillars: leave out the base. (3) Halve diameter to get r. (4) Combined solids: add volumes, but do not add hidden faces.
Area and Volume • Grade 10 Mathematics

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