How to solve problems with discount applied twice in the same product?

Follow these steps: 1) Use the original price given, multiplying it by [(100-first discount percentage) over 100] This is done to get the discounted price when the discount is applied once. 2) Use the discounted price found in the previous step and multiply it by [(100-second disctount percentage) over 100] This is done to find the final price of the product when the discount is applied twice. For example, in a clothing department a type of cloth costs £100. The manager decides to reduce its price by 50% due to decrease in demand. After a month, the demand is still low so the manager decides to reduce its price by a further 20%. Following the steps mentioned above: 1) discounted price(after first discount) = 100 * [(100-50) over 100] = 100* 0.5 = £50 2) final price = 50 * [(100-20) over 100] = 50 * 0.8 = £40