Percentages
Per cent means 'out of 100'.
Percentages of amountsIncrease & decreasePercentage change
📖 Learn
Find 10%
÷ 10. Then build: 30% = 3 × 10%, 5% = half of 10%.
Multipliers
Increase by 20% → × 1.2. Decrease by 20% → × 0.8.
% change
(change ÷ original) × 100.
Worked example
Increase £80 by 15%
- 110% = £8, 5% = £4 → 15% = £12
- 280 + 12
- 3= £92 ✅
⭐ Practise
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