Course content varies from course to course and can go from and hour to many hours of content.
For example the OTL Licensing Course has 43 lessons which include presentations, quizzes, assignments and 5 agent practice exams. Even if a student was to spend 30 minutes on each lesson, this would amount to over 20 hours of learning material.
Students can undertake course completely at their own pace; time to complete varies therefore from student to student.