Question

A store is having a sale to celebrate President’s Day. Every item in the store is advertised as one- fourth off the original price. If an item is marked with a sale price of , what was its original price?

Answer 1

If the discount is one fourth off, it means the discount is 1/4 = 25% of the original price, so the final price will be 75% or 3/4 of the original price.

In order to find the original price, we just need to divide the final price by 3/4, this way we "remove" the discount.

For example, if the sale price is $75, the original price would be:

`\text{original price}=(75)/((3)/(4))=75\cdot(4)/(3)=25\cdot4=100`

So for a sale price of $75, the original price would be $100.

In general, for a discount of x%, the original price (given the sale price) can be calculated as:

`\text{original price}=\frac{\text{sale price}}{1-(x)/(100)}`