Oliver treated his sister to lunch while visiting her in Cedarburg. Their lunch cost $275, and the sales tax in Cedarburg is 12%. If Oliver left a 20% tip on the $275, how much in total did he pay?

Oliver paid a total of $363.

Step-by-step explanation:

The total amount paid by Oliver on this dinner is given by the cost of their lunch (275) plus the tax (12%) plus the tip (20%). So in order to calculate this value we first need to know how much was paid in tax and the tip, these calculations are shown bellow:

tax = 275*12% = 275 * (12/100) = 33

tip = 275*20% = 275 * (20/100) = 55

So the total amount paid was:

total = 275 + 33 + 55 = $363

Oliver paid a total of $363.