Mensuration: Cubes, Cuboids, Cones and Cylinders | Form 1 Mathematics

Mensuration: Cubes, Cuboids, Cones and Cylinders

Mensuration measures lengths, areas and volumes of solid figures. Use consistent units and show the formula before substituting values.

Formulas

• Cube: volume V = a³ and total surface area TSA = 6a².
• Cuboid: V = lwh and TSA = 2(lw + lh + wh).
• Cylinder: V = πr²h and curved surface area = 2πrh.
• Cone: V = 1/3πr²h. Use π ≈ 22/7 or 3.142 when instructed.

Worked examples

1. A cuboid 5 cm by 3 cm by 2 cm has volume 5 × 3 × 2 = 30 cm³.
2. A cube of side 4 cm has TSA 6 × 4² = 96 cm².
3. A cylinder with r = 3 cm and h = 10 cm has volume approximately 3.142 × 9 × 10 = 282.78 cm³.

Practice

1. Find the volume and surface area of a cube of side 7 cm.
2. Find the volume of a cuboid 8 m by 2 m by 1.5 m.
3. Find the volume of a cone with radius 3 cm and height 8 cm.