Answer:
You should leave a $9.45 tip.
Explanation:
Here is a simple way to do this. Break it down into easy percentages.
$52.50 is a 100% tip.
$5.25 is a 10% tip.
$.525 is a 1% tip.
Multiply $.525 by 8 to get an 8% tip.
The answer to that will be $4.20.
Now add $4.20 and $5.25 to get an 18% tip.
Your answer is $9.45.