Percentages — Grade 4 Mathematics
Per cent means "out of 100." Understanding percentages lets us describe parts of a whole in a clear, universal way. In Grade 4, we find key percentages of amounts and connect them to fractions and decimals.
Percentages, Fractions and Decimals
Every percentage can be written as a fraction with denominator 100 and as a decimal.
| Percentage | Fraction | Decimal | Find it by… |
|---|---|---|---|
| 50% | ½ | 0.5 | ÷ 2 |
| 25% | ¼ | 0.25 | ÷ 4 |
| 75% | ¾ | 0.75 | ÷ 4, × 3 |
| 10% | ¹⁄₁₀ | 0.1 | ÷ 10 |
| 1% | ¹⁄₁₀₀ | 0.01 | ÷ 100 |
💡 Build percentages: 30% = 3 × 10% — find 10%, then multiply. 35% = 25% + 10%.
Finding a Percentage of an Amount
Method: Find 1% first (÷ 100), then multiply by the percentage you need.
Or use known facts: 10% = ÷10; 50% = ÷2; 25% = ÷4.
Or use known facts: 10% = ÷10; 50% = ÷2; 25% = ÷4.
Visual: 75% of a bar — three-quarters shaded
Worked Examples
Example 1 — Using Known Facts
Find 25% of 360.
- 25% = ÷ 4
- 360 ÷ 4 = 90
- Check: 90 × 4 = 360 ✓
Example 2 — Build from 10% and 1%
Find 35% of 420.
- 10% of 420 = 420 ÷ 10 = 42
- 30% = 3 × 42 = 126
- 5% = 42 ÷ 2 = 21
- 35% = 126 + 21 = 147
Example 3 — Real World: Sale Discount 🏷️
A jacket costs £80. It is reduced by 15%. How much do you save?
- 10% of £80 = £8
- 5% of £80 = £4
- 15% = £8 + £4 = £12 saving
- Sale price = £80 − £12 = £68
Practice Questions
1. Find 50% of 240.
✅ 240 ÷ 2 = 120
2. Find 25% of 180.
✅ 180 ÷ 4 = 45
3. Find 10% of 350.
✅ 350 ÷ 10 = 35
4. Find 30% of 500.
✅ 10% = 50; 30% = 50 × 3 = 150
5. A school has 400 pupils. 75% take the bus. How many pupils is that?
✅ 25% of 400 = 100; 75% = 100 × 3 = 300 pupils
Key Points to Remember
- Per cent = out of 100; 45% = ⁴⁵⁄₁₀₀ = 0.45.
- 50% = ÷ 2; 25% = ÷ 4; 10% = ÷ 10; 1% = ÷ 100.
- Build any percentage: 30% = 3 × 10%; 15% = 10% + 5%.
- 5% is half of 10%; 75% = 50% + 25%.
- Always label your answer with the correct units (£, kg, pupils, etc.).