Jessie buys his co-workers 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 the tax
First, calculate the pre-tax cost of the food by dividing the total cost by 1 plus the tax rate: $105.79 / 1.09 = $97.11
Then calculate the tip amount by multiplying the pre-tax cost by the tip rate: $97.11 * 0.2 = $19.42
Then calculate the total cost including tax by adding the pre-tax cost and the tip: $97.11 + $19.42 = $116.53. Answer: \boxed{116.53}.