Jesse buys his coworkers lunch from the local steakhouse. The food costs $105.79, and the sales tax rate is 9%. Jesse wants to leave a 20% tip based on the pre-tax amount. How much will the total be, including tax and tip?.
First find the pre-tax amount by dividing the total cost by 1+ the tax rate: $105.79 / 1.09 = $97
Then multiply this amount by the tip percentage to find the tip amount: $97 * .2 = $<<97*.2=19.40>>19.40
Then add the cost of the food + the cost of the tip to find the total cost: $19.40 + $97 + $105.79 = $222.19. Answer: \boxed{222.19}.