Is there a way to create a dropdown box with numbers, that once selected, creates that amount of rows to fill out on a form?

What I'm wanting to do is create an inventory-like form to keep up with computer information. Example: If the front desk computer has 4 programs that have different backup locations, I'd like to have a form where I put that computer name, then click 4 in the dropdown box. Once 4 is selected, then 4 rows appear to the right for me to put each save path. Not all computers have the same amount of backups, so creating a form with 4 or more lines for each computer just ends up taking up a bunch of space.

I hope I explained what I wanted clearly.

Thanks!

Mason <-----noob