Randomising Questions but in blocks of 20

Hello,

I hope all is well where you are. I'm having an issue wrapping my head around how to randomise a set of questions in Quiz Maker.

Here is what we need to accomplish.....we have take questions from four multiple choice exams. There are eighty in total. Each paper has 20 questions. What I need to do is set up Quiz Maker to serve one "exam paper" of 20 set questions when a learner starts the exam.

Each exam paper will have twenty questions in total but we can't randomise the entire 80 questions...they have to be exactly the way the exam papers are.

"Exam Paper 1" would consist of questions 1-20 (which are randomised).

"Exam Paper 2" should consist of questions 21-41 (also randomised).

"Exam Paper 3" should consist of questions 41-60.

"Exam Paper 4" should be questions 61-80 (randomised)

Each time a learner takes the exam, then need to be served a random "Exam Paper" from the 4 papers.

How do I set that up? If randomised each "exam paper" is a problem, we can skip that part.

I know it will have to do with locks and the randomisation button but I'm a but lost with this.

Any thoughts?

Many thanks!

Dave