Mr. P follows this rule when tipping at restaurants:
He figures 20% of the bill (food plus tax),
and then he rounds up to the nearest dollar.
If Mr. P tips $8.00, what is the total amount of his bill
(food plus tax plus tip)?
Give the entire range of values that work.
Solution to the Problem:
The total amount of the bill could be any amount from $43.01 to $48.00 inclusive.Let x = cost of the food plus tax.
Then solve .20 x = 8.00 to get x = $40.00.
Then solve .20 x = 7.00 to get x = $35.00.
So, the values of x that result in a tip of $8.00 would be
any amount over $35.00 and less than or equal to $40.00.
Then add the $8.00 tip to the values of x to get the total.
Correctly solved by:
| 1. William Vargo | Calgary, Alberta, Canada |
| 2. James Alarie | Flint, Michigan |