What is 40% of 20?
40% of 20 =
8
Step-by-step workings
Why this works
To find 40% of 20, we first convert the percentage to a decimal. 40% means 40 out of every 100, so we divide 40 by 100 to get 0.4. We then multiply this decimal by 20 to find our answer of 8.
This works because a percentage is simply a fraction of 100. 40% is the same as the fraction 2/5 (two fifths). Multiplying any number by 0.4 gives you exactly 40 parts out of every 100 of that number.
Result = (40 ÷ 100) × 20
Result = 0.4 × 20 = 8
How to check your answer
To verify that 8 is 40% of 20, divide the answer by 20 and multiply by 100:
(8 ÷ 20) × 100 = 40%
This confirms the answer is correct. Dividing the part by the whole and multiplying by 100 is the standard way to find what percentage one number is of another.
How to calculate 40% of 20 without a calculator
40% = 10% × 4. Find 10% first, then multiply by 4.
Or find 50% (10) then subtract 10% (2): 10 − 2 = 8.
40% in context
40% is less than half. It means 40 parts out of every 100. As a fraction it is 2/5 (two fifths). As a decimal it is 0.4.
| Form | Value |
|---|---|
| Percentage | 40% |
| Decimal | 0.4 |
| Fraction | 2/5 |
| 40% of 20 | 8 |
Real world examples
40% off a £20 item
A retailer offers 40% off a product priced at £20. The saving is £8, so the sale price is £12.
Saving 40% of a £20 budget
If you put aside 40% of a £20 monthly budget, you save £8 each month. Over a year that adds up to £96.
40% income tax on £20
Paying 40% income tax on £20 of taxable earnings means £8 goes to HMRC, leaving £12 after tax.
More calculations using 40%
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Related calculators and guides
- Use our percentage of a number calculator to calculate any percentage of any number instantly.
- To find what percentage of your income 20 represents, try the percent of income calculator.
- Want to understand how percentages work? Learn how to calculate percentages for GCSE with worked examples and revision notes.