There are certain mathematical calculations used in the bidding, play and defense. It is important to use them correctly. They help us to decide which card to play, which defense to develop and what offensive strategy to use. They can make the difference to bring home or to beat a contract.
| Rule of 2 & 3 |  | Rule of 2,3,4 |  | Rule of  2,3,4 b |  | Rule of 2-4-3 |
| Â | Â | Â | Â | Â | Â | Â |
| Rule of 7 | Â | Rule of 8 | Â | Rule of 9 | Â | Â |
| Â | Â | Â | Â | Â | Â | Â |
| Rule of 9b | Â | Rule of 10 | Â | Rule of 11 | Â | Â |
| Â | Â | Â | Â | Â | Â | Â |
| Rule of 11 -12 -13 | Â | Rule of 12 | Â | Rule of 13 | Â | Â |
| Â | Â | Â | Â | Â | Â | Â |
| Rule of 14 | Â | Rule of 14b | Â | Rule of 15 | Â | Â |
| Â | Â | Â | Â | Â | Â | Â |
| Rule of 17 | Â | Rule of 18 | Â | Rule of 20 (1) | Â | Â |
| Â | Â | Â | Â | Â | Â | Â |
| Rule of 20 (2) | Â | Rule of 22 | Â | Rule of 40 | Â | Â |
| Â | Â | Â | Â | Â | Â | Â |
| Rule of 64 | Â | Rule of Majority | Â | Â | Â | Â |
| Â | Â | Â | Â | Â | Â | Â |
| Never Put Down an 8-Card Suit in Dummy | ||||||
Esta entrada también está disponible en: Spanish