0.5 x 100 = 50
0.5 times 100 is 50. Multiplying by 100 moves the decimal point two places to the right, so 0.5 becomes 50. That is also the arithmetic behind reading 0.5 as 50 percent.
0.5 × 100 = 50
Two ways to see it
0.5 is one half, and half of 100 is 50. Or move the point: 0.5 becomes 5.0 after one place and 50 after two. Multiplying by 100 always means two places to the right, whatever the decimal happens to be.
This is the decimal-to-percent step
Converting a decimal into a percentage is exactly this multiplication. 0.5 x 100 = 50, so 0.5 is 50 percent. Any decimal that comes out of a division becomes a percentage the same way.
| Decimal | Times 100 | As a percent |
|---|---|---|
| 0.1 | 10 | 10 percent |
| 0.2 | 20 | 20 percent |
| 0.5 | 50 | 50 percent |
| 0.9 | 90 | 90 percent |
| 1.5 | 150 | 150 percent |
The slip to watch
0.05 x 100 = 5, not 50. One extra zero after the point divides the answer by ten. Count the digits after the decimal point before you shift them: 0.5 has one, 0.05 has two.
More decimals through 100
Try 2.5 x 100 = 250, or work down the full list on the answers index.