| Places | Ones | Tenths | Hundredths | Thousandths | Ten Thousandths | Hundred Thousandths | Millionths | Ten Millionths | |
|---|---|---|---|---|---|---|---|---|---|
| 1 | |||||||||
| Number | 0 | . | 4 | 2 | 0 | 5 | 3 | 2 | 2 |
| Rounded Number | 0 | . | 4 | 2 | 1 |
- 0 is in the thousandths place and 5 is in the ten thousandths place
- Since the digit in the ten thousandths place (5) is greater than or equal to 5, add 1 to the digit in the thousandths place (0)
- 1 + 0 = 1, so the digit in the thousandths place becomes 1
- The digits to the right of the thousandths place are dropped
- 0.4205322 rounded to the nearest thousandth (three decimal places) = 0.421
