How To: Solve reverse percentage problems

We know the method for answering the question "What is the x percent of y" but, what about the answer to the following question "The x percent discounted price of an article is y. Find the original price." This is a reverse percentage problem that can be solved using the method shown in this video. This video contains three reverse percentage problems. The first two problems are essentially of the same type as explained above. A simple and easy to understand method of finding the original price is explained in this video. The final problem is a bit different and is of the following type: "The cost of an article inclusive of x percent tax is y. Find the original price.". Again the method used is simple and easy to understand.