You can use subtraction to calculate a percentage discount. In fact, when you hear the words discount or sale price, you should automatically think of subtraction. Here’s an example:
Greg has his eye on a television with a listed price of $2,100. The salesman offers him a 30% discount if he buys it today. What will the television cost with the discount?
In this problem, you need to realize that the discount lowers the price of the television, so you have to subtract:
Sale price = 100% of regular price – 30% of regular price
Now subtract percentages:
Sale price = (100% – 30%) of regular price = 70% of regular price
At this point, you can fill in the details, as follows:
Sale price = 0.7 x $2,100 = $1,470
Thus, the television will cost $1,470 with the discount.