Well, in my stats course most of the quizzes have just one question, drawn randomly from a certain category. the students can redo the quiz unlimited and everytime they see a different question. Either the numbers have changed or the complete question is different.
the questions are 'calculated questions', you can create them in Moodle using variables.
BUT you can also generate these questions from MS Excel
By doing so you'll have the mathematical power of excel, create one question with variables in a sheet and generate for example 100 sets of data for the variables.
Look at this https://sites.google.com/site/cq4mgenerator/
some examples are there
it might be a bit cryptical to start with but find me and I'll happily help you out
succes
Hiram