For example, a three number bet means dividing 36 by 3 to get 12, then subtracting 1 to equal 11. The payout rate for a three number bet is therefore 11:1, meaning aR$10 bet would result in aR$120 payout if you won.
The roulette probability of correctly predicting the winning number in the European variant is 1-in-37, or about 2.70%. If you play for 30 rounds, you have a 55% chance of getting the number right at least once.
Games like Blackjack, Craps, Baccarat, and Roulette give you the best odds of winning. The Wheel of Fortune and Keno give you the worst odds of winning. Table games always have better odds than slot machines.