How to find 45 percent of 20
"Percent" means per hundred, so 45% is the fraction 45/100, or 0.45 as a decimal. Taking 45 percent of 20 means multiplying 20 by that fraction:
45% of 20 = 20 x 45 / 100
= 900 / 100
= 9The same answer comes from the decimal form: 20 x 0.45 = 9. And because multiplication is commutative, 45% of 20 equals 20% of 45, which is sometimes the easier way to see it in your head.
Mental math shortcut
10% of 20 is 2 (move the decimal one place left), and 1% is 0.2. Build 45% from those pieces: 4 x 2 + 5 x 0.2 = 9.
Nearby percentages of 20
| Percent | Of 20 | 20 minus it | 20 plus it |
|---|---|---|---|
| 1% | 0.2 | 19.8 | 20.2 |
| 5% | 1 | 19 | 21 |
| 10% | 2 | 18 | 22 |
| 15% | 3 | 17 | 23 |
| 20% | 4 | 16 | 24 |
| 25% | 5 | 15 | 25 |
| 30% | 6 | 14 | 26 |
| 40% | 8 | 12 | 28 |
| 44% | 8.8 | 11.2 | 28.8 |
| 46% | 9.2 | 10.8 | 29.2 |
| 50% | 10 | 10 | 30 |
| 75% | 15 | 5 | 35 |
45 percent of other amounts
| Amount | 45% of it |
|---|---|
| 10 | 4.5 |
| 25 | 11.25 |
| 30 | 13.5 |
| 40 | 18 |
| 50 | 22.5 |
| 60 | 27 |
| 75 | 33.75 |
| 80 | 36 |
| 100 | 45 |
Where this comes up
A 45% discount on a 20 price takes off 9, leaving 11. A 45% tip or tax on 20 adds 9, for a total of 29. If 20 is a score out of a possible total, 45% of it is the share 9 represents. For percent change, reverse percentages, and "X is what percent of Y", use the full percentage calculator.