Jess buys his coworkers lunch from the local steakhouse. The food costs $105.79, and the sales tax rate is 9%. Jess wants to leave a 20% tip based on the pre-tax amount. How much will the total be, including tax and tip?
The sales tax on the food is $105.79 * 9% = $<<105.79*9*.01=9.53>>9.53.
The pre-tax amount is $105.79 - $9.53 = $<<105.79-9.53=96.26>>96.26.
The tip is 20% * $96.26 = $<<20*.01*96.26=19.252>>19.252
Thus, the total amount, including tax and tip, will be $105.79 + $9.53 + $19.25 = $<<105.79+9.53+19.25=134.57>>134.57. Answer: \boxed{134.57}.