THEM: i need the books and the balls  YOU: ill give you both balls for the books.  THEM: that is not going to work - i need both books and 1 ball minimum  YOU: in that case ill take the hat and both balls  THEM: thats fine as long as i can get both books  YOU: naw thats too easy no deal  THEM: okay well then i need both books and a ball. or both balls and a book.  YOU: i can give you both balls and a book  THEM: deal.