Tabla del -20
| -20 | X | 1 | = | -20 |
| -20 | X | 2 | = | -40 |
| -20 | X | 3 | = | -60 |
| -20 | X | 4 | = | -80 |
| -20 | X | 5 | = | -100 |
| -20 | X | 6 | = | -120 |
| -20 | X | 7 | = | -140 |
| -20 | X | 8 | = | -160 |
| -20 | X | 9 | = | -180 |
| -20 | X | 10 | = | -200 |
| -20 | X | 1 | = | -20 |
| -20 | X | 2 | = | -40 |
| -20 | X | 3 | = | -60 |
| -20 | X | 4 | = | -80 |
| -20 | X | 5 | = | -100 |
| -20 | X | 6 | = | -120 |
| -20 | X | 7 | = | -140 |
| -20 | X | 8 | = | -160 |
| -20 | X | 9 | = | -180 |
| -20 | X | 10 | = | -200 |