Calculated Questions
You can add a Calculated Question to your survey that is not displayed to the user but rather returns a calculation based on other questions in your survey. For example, you can use a Calculated Question to calculate a score based on responses to questions in a survey. A Calculated Question is not shown to the user (although its value could be piped if you want the user to see it) but otherwise is treated just like any other question in your survey, meaning you will see its value in results analysis and you can use it in Piping, Ask If Logic and other formulas.
Adding a Calculated Question
Here are the steps to add a calculated question to a survey
 Insert a new question and choose Text Box (if the formula will return textual data) or Number Box (if the formula will return numeric data) from the Gallery.
 In the Question field, insert the formula for the question, using the formula syntax, i.e:
 <{formula_here}>
 For more information on formulas see Formulas.
 Click OK to save the formula. Your question should look something like this:
