Mathematics · Class 8
Mensuration
Surface area and volume of cube, cuboid, cylinder, and composite solids.
4 sections15–25 min read6 MCQs · 2 examples
Chapter Overview
Class 8 mensuration covers surface area and volume of cuboid, cube, cylinder — applied to water tanks, packaging, and room painting in Indian contexts.
Cuboid and Cube
Cuboid volume
V = l × b × h
Cube volume
V = a³
TSA cube
6a²
CSA cylinder
2πrh
Cylinder
TSA
2πr(r + h)
Volume
πr²h
Capacity
1 litre = 1000 cm³ = 1 dm³. Water tank problems convert between litres and m³.
Solved Examples
Step-by-step solutions — read each step before checking the final answer.
Example 1: Cylinder Volume
Cylinder r=7 cm, h=10 cm. Volume (π=22/7).
- 1V = πr²h
- 2= 22/7 × 49 × 10
Answer
1540 cm³
Example 2: Cuboid TSA
Cuboid 5×4×3 cm. Total surface area.
- 1TSA = 2(lb+bh+hl)
- 2= 2(20+12+15)
Answer
94 cm²
Key Points to Remember
- ✓ CSA excludes top/bottom where applicable
- ✓ Convert units before calculating
- ✓ Painting problems use surface area
Exam Tips
- • State whether TSA or CSA asked
- • Include π value as directed
Practice MCQs — Mensuration
Test your understanding with topic-wise multiple choice questions. Explanations appear after each answer.
Question 1 of 6Score: 0/0
Volume of cube side 5 cm: