Answer: 60 dollars
Explanation:
Since both the sales tax and the tip apply to the original price of the dinner, we can add the two rates.
11% + 20% = 31%
Next we need to find what number 18.60 is 31% of.
Since percent means per hundred 31% is equal to .31.
Now we need to now what number times .31 + 18.60
Divide both sides by .31.
The .31 will be cancelled out and $18.60 will become $60.
$18.60 is 31% of $60