Jesse buys his coworkers lunch from the local steakhouse. The food cost $105.79 and the sales tax rate is 9%. Jesse wants to leave a 20% tip based on the pre-taxed amount how much will the total be including tax and tip.
The tax on the food will be $105.79 * 0.09 = $<<105.79*0.09=9.53>>9.53.
Adding the pre-tax cost and the tax, the total will be $105.79 + $9.53 = $<<105.79+9.53=115.32>>115.32.
To determine the tip, we first need to find the pre-tax cost. To do this, we subtract the tax from the total: $115.32 - $9.53 = $<<115.32-9.53=105.79>>105.79.
Finally, to calculate the tip, we multiply the pre-tax cost by 0.20: $105.79 * 0.20 = $<<105.79*0.20=21.16>>21.16.
Adding the tip to the pre-tax cost and the tax, the total including tax and tip will be $105.79 + $9.53 + $21.16 = $<<105.79+9.53+21.16=136.48>>136.48. Answer: \boxed{136.48}.