Roulette delay in dozens and columns
Dozens and columns are bets to twelve numbers. The probability of winning a dozen bet is 32.34%, there is a 67.57% chance of losing. The probability of winning at least once in two spins is 54.35% and in twelve spins is 99%. This means that if we bet to dozens or columns, we can win (with 99% probability) at least once every 12 spins. This 12 number is the theoretical delay of dozens. It can be seen in the following table and figure.
According to our calculations, the same dozen appears twice consecutively between 7 and 42 minutes. Between one hour to 7 hours of play at roulette, we can observe 4 consecutive repetitions of the same dozen.