THEM: what if i take 1 book, 1 hat and 1 ball  YOU: i need the hat. if i can have the hat and two balls you can have two books and one ball  THEM: sorry but i also need the hat  YOU: then can i take all of the balls and one book and you can have the hat and one book  THEM: what if i take the hat and 2 books. you get all the balls  YOU: okay that works! thank you!