Calculator Use
Calculate the list price, discount percentage or sale price given the other two values. You will also find the discount savings amount.
Calculate Discount from List Price and Sale Price
The discount is list price minus the sale price then divided by the list price and multiplied by 100 to get a percentage.
\(D = \dfrac{(L - S)}{L} \times 100 \)
Where:
- L = List Price
- S = Sale Price
- D = Discount percentage
Example
If the list price of an item is $120 and the final sale price is $90 then discount is calculated as follows:
\(D = \dfrac{(L - S)}{L} \times 100 \)
\(D = \dfrac{(120 - 90)}{120} \times 100 \)
\(D = \dfrac{30}{120} \times 100 \)
\(D = 0.25 \times 100 \)
\(D = 25\% \)
\(\text{Amount Saved} = $120 - $90 = $30 \)
Calculate Sale Price from List Price and Discount
The sale price is the list price minus the product of the discount divided by 100 and multiplied by the list price.
\(S = L - \dfrac{D}{100} \times L \)
Example
If the list price of an item is $120 and discount is 75% then the final sale price is calculated as follows:
\(S = L - \dfrac{D}{100} \times L \)
\(S = 120 - \dfrac{75\%}{100} \times 120 \)
\(S = 120 - 0.75 \times 120 \)
\(S = 120 - 90 \)
\(S = 30 \)
\(\text{Amount Saved} = $120 - $30 = $90 \)
Calculate List Price from Discount and Sale Price
The list price is the sale price divided by the difference of 1 minus the result of discount divided by 100.
\(L = \dfrac{S}{(1 - \dfrac{D}{100})} \)
Example
If the sale price of an item is $40 and the discount is 20% then the list price is calculated as follows:
\(L = \dfrac{S}{(1 - \dfrac{D}{100})} \)
\(L = \dfrac{40}{(1 - \dfrac{20\%}{100})} \)
\(L = \dfrac{40}{(1 - 0.20)} \)
\(L = \dfrac{40}{0.80} \)
\(L = 50 \)
\(\text{Amount Saved} = $50 - $40 = $10 \)
Sample Discount Percentage Calculation
James bought a vintage lava lamp at a sale price of $89.63. The original price was $165.99. What was the percentage discount on the original price of the lava lamp?
Using the formula above, list price = L = 165.99, and price sale = P = 89.63.
\( \dfrac{(165.99 - 89.63)}{165.99} \times 100 = 46 \)
James got a 46% discount on the lava lamp.
