Understanding the concept
Volume measures three-dimensional space. Capacity describes how much a container can hold, commonly in litres or millilitres. The same volume may be written using cubic units.
Before calculating, decide what the measurement describes, identify the starting units and choose a sensible level of precision.
Step-by-step method
For a rectangular box, volume = length × width × height, using consistent units. Remember 1 L = 1,000 mL = 1,000 cm³.
- Write down the original measurement and its unit.
- Choose the formula or conversion factor appropriate to the task.
- Calculate carefully, keeping the units visible at each step.
- Check the answer against an estimate and the real-world situation.
Quick-reference table
Keep these facts handy when solving measurement questions.
| Measurement | Equivalent or interpretation |
|---|---|
| 1 litre | 1,000 mL |
| 1 mL | 1 cm³ |
| 1 m³ | 1,000 L |
| 1,000 cm³ | 1 L |
Four worked examples
Each example shows the calculation and the units used.
Example 1: Water bottle
Example 2: Fish tank
Example 3: Storage box
Example 4: Water use
Common mistakes
Check for these problems before finalising your answer.
- Using square units for volume.
- Multiplying dimensions expressed in different units.
- Assuming a container can be filled to its exact external dimensions.
Practice questions
Try these without looking at the answers first.
Question 1. Convert 3 L to mL.
Show answer and explanation
3,000 mL.
Question 2. Convert 250 mL to litres.
Show answer and explanation
0.25 L.
Question 3. Volume of 2 cm × 3 cm × 4 cm?
Show answer and explanation
24 cm³.
Question 4. Convert 0.5 m³ to litres.
Show answer and explanation
500 L.
Question 5. How many 200 mL cups make 1 L?
Show answer and explanation
5 cups.
Review checklist
- Can you name the unit and explain what is being measured?
- Can you choose the correct formula or conversion factor?
- Can you show your calculation and units clearly?
- Can you check whether the answer is realistic?