Translations:Expression Manager - presentation/63/en
From LimeSurvey Manual
Yet, there is a way to use both expressions and conditions within a question. As mentioned above, a condition replaces the relevance equation field. Once done, check what is the newly created equation and copy it in a text editor. Delete the newly created condition from the Conditions editor and then edit the question by adding the condition-based expressions from your text editor file alongside the rest of expressions you wish to use.