If you belive more in math than in randomnes you should play martingale. What is the odds of red popping up yet another time...
50%
Yeah, but there's already been a lot of reds. Clearly you don't understand probability. Eventually there has to be a black, and since there's been so many reds it's very unlikely it will continue to be red.
So the chances are *way* less than 50%. Black is a sure bet.