ok what if the ratio is 5x/6, is there another formula i can use? this is for solving the sum of:
x * (1/6) * (5/6)^(x-1) where x is 1 to infinity
To be honest, I cannot say that I really follow what you are trying to do.
Here is an example: $\displaystyle \sum\limits_{x = 1}^\infty {\left( {\frac{5}{6}} \right)^x } = \frac{{\frac{5}{6}}}{{1 - \frac{5}{6}}}$