give the formula used

Given the following parameters what is the APR of the following investment? Assume end of month investments. without the \\%; round your final answer to two decimals. \\( \\begin{array}{lc}\\text { Investment: } & \\$ 104.00 \\\\ \\begin{array}{l}\\text { Frequency of investment: } \\\\ \\text { Term: }\\end{array} & \\text { Monthly } \\\\ \\text { Payoff at the end of the term: } & \\$ 66,245.00\\end{array} \\)