This web app enables you to practice pharmacy calculation problems of a given type for unlimited times. You will only see the change in the numbers but not the skeleton of the problem. I call this "Shadow method" of practicing over and over. The questions are arranged in both table view and list view (to be accessed from the left panel). When a question type is clicked, it opens with its title, hierarchy, main body of the question and four options. It also has a button to retry. You can select an option and submit to verify correctness. At this point, a new button named "Explanation" is visible, which shows you how this problem was solved.