Would like to merge files - each file is a picture of a person. I would like to put about 5 pictures across the page and 5 rows of pictures per page. Please let me know how to do this. The dimensions of the pictures are 640 x 480, the size is 147 and they are JPEG's. I have a pc with adobe acrobat pro X
You're using the wrong application. Do it in a word processing program like Microsoft Word, or in a page layout application like Adobe InDesign.
Acrobat Pro is a program for editing and working with PDF files.
Choose the correct tool for the job.
If you have the files in a PDF, you can merge (insert pages) them (or insert pages from graphics files). Then print to a new PDF with multiup selected for the number per page. Not the cleanest way, but would do what you want. A layout program is a better approach.