Talen 681 till 687 i romerska siffror
I högerkolumnen visas hur varje romersk siffra bidrar till att man hamnar vid rätt tal.
| 681 | = | DCLXXXI | = | 500 + 100 + 50 + 10 + 10 + 10 + 1 |
| 682 | = | DCLXXXII | = | 500 + 100 + 50 + 10 + 10 + 10 + 1 + 1 |
| 683 | = | DCLXXXIII | = | 500 + 100 + 50 + 10 + 10 + 10 + 1 + 1 + 1 |
| 684 | = | DCLXXXIV | = | 500 + 100 + 50 + 10 + 10 + 10 + 5 − 1 |
| 685 | = | DCLXXXV | = | 500 + 100 + 50 + 10 + 10 + 10 + 5 |
| 686 | = | DCLXXXVI | = | 500 + 100 + 50 + 10 + 10 + 10 + 5 + 1 |
| 687 | = | DCLXXXVII | = | 500 + 100 + 50 + 10 + 10 + 10 + 5 + 1 + 1 |