I understand you have a multiple-choice type of question with five radio buttons, all grouped within a button set. Why calculate anything when you can directly set a score upon clicking any radio button? For instance, if you click Radio button 1, set the score to "1"; if you click Radio button 2, set the score to "2," and so forth. Then, upon clicking the Submit button, display different layers based on the value of the score variable. Calculations (adding and subtracting from the score variable value) would be more relevant if you had a multiple-response type of question where you can select and deselect multiple checkboxes simultaneously.