How to find 20 percent of 40
"Percent" means per hundred, so 20% is the fraction 20/100, or 0.2 as a decimal. Taking 20 percent of 40 means multiplying 40 by that fraction:
20% of 40 = 40 x 20 / 100
= 800 / 100
= 8The same answer comes from the decimal form: 40 x 0.2 = 8. And because multiplication is commutative, 20% of 40 equals 40% of 20, which is sometimes the easier way to see it in your head.
Mental math shortcut
10% of 40 is 4 (move the decimal one place left), and 1% is 0.4. Build 20% from those pieces: 2 x 4 = 8.
Nearby percentages of 40
| Percent | Of 40 | 40 minus it | 40 plus it |
|---|---|---|---|
| 1% | 0.4 | 39.6 | 40.4 |
| 5% | 2 | 38 | 42 |
| 10% | 4 | 36 | 44 |
| 15% | 6 | 34 | 46 |
| 19% | 7.6 | 32.4 | 47.6 |
| 21% | 8.4 | 31.6 | 48.4 |
| 25% | 10 | 30 | 50 |
| 30% | 12 | 28 | 52 |
| 40% | 16 | 24 | 56 |
| 50% | 20 | 20 | 60 |
| 75% | 30 | 10 | 70 |
20 percent of other amounts
| Amount | 20% of it |
|---|---|
| 10 | 2 |
| 20 | 4 |
| 25 | 5 |
| 30 | 6 |
| 50 | 10 |
| 60 | 12 |
| 75 | 15 |
| 80 | 16 |
| 100 | 20 |
| 120 | 24 |
Where this comes up
A 20% discount on a 40 price takes off 8, leaving 32. A 20% tip or tax on 40 adds 8, for a total of 48. If 40 is a score out of a possible total, 20% of it is the share 8 represents. For percent change, reverse percentages, and "X is what percent of Y", use the full percentage calculator.