The answer is They left a 20% tip, so the service was probably above average. First step is to the amount of the sales tax. If 100% is $73.89, 5.8% will be x (tax): 100% : $73.89 = 5.8% : x. x = $73.89 * 5.8% : 100%. x = $4.28. Now, we have the price for meals, sales tax, and the total amount of money left, so we can calculate how much the tip is: $93.00 - $73.89 - $4.28 = $14.83. So, the tip is $14.83. Let represent it as percent. If $73.89 is 100%, $14.83 will be x. $73.89 : 100% = $14.83 : x. x = $14.83 * 100% : $73.89. x = 20%. So, they left a 20% tip, so the service was probably above average.
