A 25.4 fl oz bottle can fill 4 60 ounce cups. How many bottles would you need to buy to fill 60 cups?

Since a 25.4 fl oz bottle can fill 4 60 ounce cups, it can fill 4/60 = 1/15 of a cup.

To fill 60 cups, you would need 60/(1/15) = 900 bottles. Answer: \boxed{900}.