You are choosing between investing a fraction of your funds in a risky stock portfolio with expected return 11.6% and a standard deviation of 20$ and a short-term risk-free investment with a one year rate of return of 2%. Your risk aversion parameter is 4 and you are an investor who makes decisions according to the standard mean-variance utility function.

What would be your initial investment if your optimal complete portfolio's expected payoff is $107,760?