How to open my Pages 3.0 documents on Pages 5
I have iWorks i08 which has Pages 3.0. I purchased Pages 5.0 on the app store, but when I try to open any of my existing Pages documents it says "This document can't be opened because it's too old. To open it, save it with Pages '09 first". However I don't have Pages '09, so how can I convert my documents? BTW I also have this same problem with my Numbers documents.
Any suggestions?
iMac, OS X Mavericks (10.9)