At a restaurant, I was given a bill for $95.11 that included a 15% gratuity.
I wanted to leave a 20% tip instead of the 15% tip already included.

How much should I add to the bill?

 

Solution to the Problem:

I should add $4.13 to the bill of $95.11 for a total of $99.24.

Let x = original bill without the 15% gratuity.
Then x + .15x = 95.11
Therefore, x = $82.70 (the price for the food)
20% of $82.70 = $16.54
15% of $82.70 = $12.41
Subtracting, you get $4.13

Correctly solved by:

1. Richard K. Johnson La Jolla, California
2. K. Sengupta Calcutta, INDIA
3. John Funk Ventura, California
4. David & Judy Dixon Bennettsville, South Carolina