Question

David takes his family to lunch at a restaurant. The bill for lunch before tax is $86.40, plus a sales tax rate of 9%. David also gives the waiter a 20% tip based on the pre-tax amount. What is the amount of the tip David gives the waiter?

Answer 1

David gave a 20% tip on the pre-tax amount of $86.40, which calculates to $17.28.

Step-by-step explanation:

David gave the waiter a 20% tip based on the pre-tax amount of the lunch bill. To calculate the amount of the tip, you first convert the percentage to a decimal. The tip percentage in decimal form is 0.20 (20% / 100). Then, multiply the decimal by the pre-tax amount, which is $86.40.

Tip: 0.20 × $86.40 = $17.28

So, the amount of the tip David gives the waiter is $17.28.