Formula for splitting an item?

My roommate and i bought a tv last year and payed equal dollars for it. Now he wants to buy a new bigger one. I had this book that had a formula for paying out the other guy, with time had, original price and some other things. The problem is i lost the book. Does anyone know what i'm talking about?Formula for splitting an item?
Forget the dam book just give him this amount if you both paid half of (100%) which is (50%) each then you need to only give him (25%) back to bye him out to own the item outright simply because he is the one who wants to get out and that is more than fair if you consider him a good friend.Formula for splitting an item?
nope sorry... looks like your going to have to find that book.

bob hair