Question

Examining Equations that Represent a Scenario

These equations represent different possibilities for a waiter earning $11.25 for waiting on one table for one hour. The constant is the hourly rate and the coefficient represents the fraction of the bill, b, the customers left as a tip. Which equation correctly represents the hourly rate and tip for a bill of $30.00?

5.00 + b = 11.25

5.25 +b = 11.25

5.25 + b = 11.25

6.00 + b = 11.25

Answer 1

5.25 + 0.2b = 11.25

Explanation: the base hourly rate is $5.25 and the customers left a 20% tip. For a $30 bill the tip is 0.2·30 = $6, and 5.25 + 6 = 11.25. (0.2 = 1/5, so 5.25 + (1/5)b = 11.25 also works.)