How do you do the work for

$43 dinner; 18% gratuity

Start by calculating just the gratuity by itself. We know its 18% of $43. Another way to write 18% is 0.18 so:



So just the gratuity by itself is $7.74. If you want to know the entire bill you can add up the meal and the gratutiy like so




Another way to do it is to recognize that you are paying for 100% of the meal and then paying antoher 18% AGAIN for a total of 118% or 1.18. If you do this you get the same