Some more information might help. If they have Reader installed, they can open them all on their own.
Did you want these to open automatically or something? Would combining the files in to one file work?
Do you have Acrobat?
The more information about what you want and what applications you have we have, the better chance that we can make a recommendation for you.
Yes Open to PDFs automatically, they will be in the same folder and I have Reader ONLY But I have a copy on USB DRive if someone needs to install it.