The most frequently sold roulette system by scammers who claim you can’t lose with it. Henry Labouchere discovered the system and named it after himself. Actually it was created by someone else but Henry didn’t care about that. This is the most famous cancellation betting system strategy and is fun to play. This section will explain how to play it and how not to get (too) hurt by playing it.
On an American wheel, there are 38 spots: numbers 1-36, plus 0 and 00. Your odds of winning a one-number bet are 37 to 1 (37 ways to lose, 1 way to win). But if you win, the casino doesn't pay you 37 to 1, they pay you less: 35 to 1. The difference between the true odds and what they actually pay you is 2/38, or 5.26%. You can do this same calculation for the other bets, and it comes out the same.