Talen 1284 till 1290 i romerska siffror
I högerkolumnen visas hur varje romersk siffra bidrar till att man hamnar vid rätt tal.
| 1284 | = | MCCLXXXIV | = | 1000 + 100 + 100 + 50 + 10 + 10 + 10 + 5 − 1 |
| 1285 | = | MCCLXXXV | = | 1000 + 100 + 100 + 50 + 10 + 10 + 10 + 5 |
| 1286 | = | MCCLXXXVI | = | 1000 + 100 + 100 + 50 + 10 + 10 + 10 + 5 + 1 |
| 1287 | = | MCCLXXXVII | = | 1000 + 100 + 100 + 50 + 10 + 10 + 10 + 5 + 1 + 1 |
| 1288 | = | MCCLXXXVIII | = | 1000 + 100 + 100 + 50 + 10 + 10 + 10 + 5 + 1 + 1 + 1 |
| 1289 | = | MCCLXXXIX | = | 1000 + 100 + 100 + 50 + 10 + 10 + 10 + 10 − 1 |
| 1290 | = | MCCXC | = | 1000 + 100 + 100 + 100 − 10 |