Calculate percentage of X, quick & simple.
Let's take a quick example here:
You have a Target coupon of $12 and you need to know how much will you save on your purchase if the discount is 90 percent.
Solution:
Amount Saved = Original Price x Discount in Percent / 100
Amount Saved = (12 x 90) / 100
Amount Saved = 1080 / 100
Amount Saved = $10.8 (answer).
In other words, a 90% discount for a purchase with an original price of $12 equals $10.8 (Amount Saved), so you'll end up paying 1.2.