I'd like is for the questions to be picked from a range - say 3 from 10 - is that possible?

Brilliant - OK, I've sorted that now and have each correctly answered question revealing the next question with the final question revealing the submit button when answered correctly - so that all works, thanks.

Now what I'd like is for the questions to be picked from a range - say 3 from 10 - is that possible?

I'm not sure if I understood your question correctly. Do you wish to skip some pages/questions based on your user's answer? If so, this guide might help: How-to-Skip-Pages-Using-Conditional-Logic 

If you are, however, referring to something else, kindly provide us more details of what you're trying to achieve and we'll be happy to help.