If a price is discounted by n percent, then the price becomes (100-n) percent of the original price.
Example 1: A certain customer paid $24 for a dress. If that price represented a 25 percent discount on the original price of the dress, what was the original price of the dress?
If p is the original price of the dress, then 0.75p is the discounted price.
0.75p = $24
p = $32
The original price of the dress was $32.
Example 2: The price of an item is discounted by 20 percent and then this reduced price is discounted by an additional 30 percent. These two discounts are equal to an overall discount of what percent?
If p is the original price of the item, then 0.8p is the price after the first discount. The price after the second discount is (0.7)(0.8p) = 0.56p. This represents an overall discount of 44 percent (100% - 56%).