Shemp has it down pretty good.
But if you end up going for a longer tour, it could be that you'll just meet up with people and end up doing a defacto "group tour" for a while. On my cross-Canada, I probably spent almost half of my time riding with various other tourers. Sometimes it would be a single person and other times it would be a small group of 3-4. I spent as little as a few hours riding with someone else to more than two weeks.