Answer:
Bill amount is $54
Explanation:
Tip is a gratuity and amount of money which a customer gives for some specific services workers on the the work they performed. It is the additional amount to the original value of the service
As per given data
Percentage of Tip = 18% = 0.18
Formula for Tip
Tip = Bill amount x Tip rate
$9.72 = Bill amount x 0.18
Bill amount = $9.72 / 0.18
Bill amount = $54