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?

To find the total cost, we need to calculate the sales tax and the tip separately and then add them to the pre-tax cost.

First, let's find the sales tax amount.
Sales Tax = (Sales Tax Rate * Pre-tax Cost) / 100
Sales Tax = (9 * 105.79) / 100
Sales Tax = 9.52

Next, let's find the tip amount.
Tip = (Tip Rate * Pre-tax Cost) / 100
Tip = (20 * 105.79) / 100
Tip = 21.16

Now we can calculate the total cost.
Total Cost = Pre-tax Cost + Sales Tax + Tip
Total Cost = 105.79 + 9.52 + 21.16
Total Cost = 136.47

Therefore, the total cost, including tax and tip, will be $136.47.

answer fr

The sales tax on the food will be $105.79 x 0.09 = $<<105.79*0.09=9.52>>9.52.

The food plus the sales tax will cost $105.79 + $9.52 = $<<105.79+9.52=115.31>>115.31.
The pre-tax amount is $115.31 / 1.09 = $<<115.31/1.09=105.99>>105.99.
The tip will be $105.99 x 0.2 = $<<105.99*0.2=21.20>>21.20.
The total cost will be $115.31 + $21.20 = $<<115.31+21.20=136.51>>136.51. Answer: \boxed{136.51}.

To find the total cost, including tax and tip, we'll need to follow these steps:

Step 1: Calculate the sales tax amount
Multiply the cost of the food by the sales tax rate (expressed as a decimal):
Sales tax = $105.79 * 0.09 = $9.52 (rounded to the nearest cent)

Step 2: Calculate the pre-tax amount
Subtract the sales tax amount from the total cost of the food:
Pre-tax amount = $105.79 - $9.52 = $96.27

Step 3: Calculate the tip amount
Multiply the pre-tax amount by the tip rate (expressed as a decimal):
Tip = $96.27 * 0.20 = $19.25

Step 4: Calculate the total cost
Add the pre-tax amount, the sales tax, and the tip together:
Total cost = $96.27 + $9.52 + $19.25 = $125.04

Therefore, the total cost of the lunch, including tax and a 20% tip, will be $125.04.