Notice the big 0? There are actually 38 slots in Roulette. 0, and 00 are extra.
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- The probability that the ball eventually ends up in one of the slots depends on how many slots there are: They are 37 (in French/European roulette) or 38 (in American roulette) colored and numbered pockets on the wheel.
- If you were simply betting on red, and if there were only black or red slots, then you would be winning with a 50% chance.
- You can run a simulation. Starting with 100 dollars, if you put 10 dollars on only red, then your 10 will become 20 if the ball goes in a red slot, and becomes zero if it goes in the black.
- Keep playing this way, and eventually you would actually run out of all the cash. You can certainly double your money, if you were lucky.
- There was once I was playing this way, and was only randomly choosing red or black, and ten times in a row I won. My cash went from about 100 to 270. In one or two of the attempts, I had also put some money on first 12. Then eventually I lost 10 dollars, and walked away from the table. But it was purely luck, and there was absolutely no strategy.
- There can actually be absolutely no strategy on Roulette. The odds are only against you.
- Some people try to come up with strategies like these: Every time it has hit three blacks, I will put money on red. That is meaningless.
- Some others try to come up with strategies like: bet in geometric progression: That is also meaningless. First, they will not allow you to do it, and second, the table is always capped with an upper limit.
- There was once I was in Vegas, and I talked to a person who was on a roulette table. It was late night and I was in no mood to play. I asked him to tell me his best stories. Usually people love to share their life’s best stories.
- He told me following (you should read with a pinch of salt, but these can be true):
- There was once in his life time he had seen the ball going to different red spots 49 times in a row. They were all different and random, but they were all red. A lot of people lost some serious cash on that table that day, because every time it would go to one more red, they would put some serious money on the blacks, and they kept losing.
- There was once a guy was doing series bets with geometric betting. It goes like this:
- Put 10 dollars.
- Win? Put 10 dollars again. Repeat.
- Lose?
- Put 20 dollars. Win? Put 10 dollars again and repeat.
- Keep doing this all the way as 10 → 20 → 40 →80→ 160. But note that Roulette tables are capped, so you cannot keep going like this. They will simply say no. And what is one of your losing bets is on 160? All that cash is gone. That happened with the guy. He kept winning for almost 3 hours in a row, but eventually it hit the green slot, and he lost a major bet. Then he just walked away.
You can read all the math, odds, payouts and so on here: https://en.wikipedia.org/wiki/Ro…
Words of caution: The odds are against you. You are far better off not playing it to double your money. You can play it for fun, and you can win a little sometimes 🙂 Sure it does give some adrenaline rush.
Also, you would learn more in your life, if you actually take a probability class in your school, work out some probability numbers, simulations in Python, and developing your own version of digital roulette, than to actually ever play roulette.