Say a single-number bet has a 35:1 payout, and you bet $1. If you win, you'll get your money back plus $35. Another example: If you win a $100 bet (for a 35:1 payout), you get a total of $3,600 ($3,500 profit plus the $100 you initially bet).
Roulette is primarily a game of luck, as the outcome of each spin is determined by random chance. The layout of the wheel and the distribution of numbers are designed to ensure randomness and make it difficult to predict where the ball will land.