Stats problem. Please format explanations clearly! Thank you in advanced (:

Try multiplying out ( x + y ) , but don't group any terms-- that is, leave every term with a coefficient of 1. How many ways did you arrive at x2 y . J And at . V Try it with ( xty )s If we relabel x and y as "left" and "right", does this relate to the Galton board? And how, then, does it relate to the underlying binomial distribution