Count cubes, calculate cuboids, find missing dimensions!
Volume is the amount of 3D space an object takes up. We measure it in cubic units: cm³, m³, mm³.
Think of filling a box with unit cubes — the number of cubes is the volume!
A cuboid (rectangular box) has length, width and height.
Units: if l, w, h are in cm → V is in cm³
If l, w, h are in m → V is in m³
A cube has equal sides. If the side length is s:
Example: cube with side 4 cm → V = 4³ = 64 cm³
If you know the volume and two dimensions, divide to find the third:
Example: V = 120 cm³, w = 5 cm, h = 4 cm
l = 120 ÷ (5 × 4) = 120 ÷ 20 = 6 cm
| Unit | Used for | Conversion |
|---|---|---|
| mm³ | tiny objects | 1 cm³ = 1000 mm³ |
| cm³ | everyday objects | 1 litre = 1000 cm³ |
| m³ | rooms, buildings | 1 m³ = 1,000,000 cm³ |
Key link: 1 ml = 1 cm³ (used in capacity)
Find the volume of a cuboid: length 8 cm, width 5 cm, height 3 cm.
Find the volume of a cube with side length 6 cm.
A cuboid has volume 180 cm³, length 9 cm, height 4 cm. Find the width.
A fish tank is 50 cm long, 25 cm wide and 30 cm tall. How many litres of water does it hold when full? (1 litre = 1000 cm³)
Calculate the volume of each cuboid. Give units.
Find the volume of each cube.
Find the missing measurement.
Convert between units or complete the statement.
Solve each problem.