Question

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 + One-sixthb = 11.25
5.25 +One-thirdb = 11.25
5.25 + One-fifthb = 11.25
6.00 + One-eighthb = 11.25

Answer 1

The third equation. Substitute b = 30:

5.25 + (1/5)(30) = 5.25 + 6 = 11.25.

So the hourly rate is $5.25 and the tip is 1/5 (20%) of a $30 bill = $6.