Copied from MDL-63260 . Log in as a teacher in a course. Create a course Turn editing on. Create a quiz Edit the quiz and add a new True/false question under the course's default question category. Add a "random question" to the quiz using the course's default question category Go back to the course page Duplicate the quiz Duplicate the quiz again Duplicate the quiz yet again Check the question table on the database. (It's most likely mdl_question). You should see 9 questions on the table. Open a terminal, go to your Moodle instance's root directory and run php admin/tool/task/cli/schedule_task.php --execute=\\qtype_random\\task\\remove_unused_questions Confirm that you see a message that 4 unused random questions have been cleaned up. Check the question table. Confirm that only 5 questions now remain.