I do not think that using math or other predictions you can win in gambling, and especially in roulette. There everything is designed for pleasure, not profit.
That is right. Math can't help you, but it can assist you in some points. There are some branches of Mathematics that can help you with these type of activities. There are the probabilities and statistics. Probability is mostly used in gambling, the proof is the percentage of win you can see whenever you roll your dices in some gambling sites, everything has their percentage of winning in gambling but it is pretty small. IN terms of Statistics, I think when most people use that kind of trick or skill and won a lot, you will be doing the same thing, you will start to search or ask some people about gambling, gather some data that can help you win.
I think Maths can help you or aiding you make some prediction by analyzing the probability especially in card games where it has a fixed number of cars as given. It requires quick thinking in making decisions and evaluating its possible combinations.