If we wish to refer to the quantity midway between the numbers one and two, we say ONE AND A HALF. Elementary as the concept is, it has taken us four words to express it. By comparison, there are a good many other languages in which just one word will suffice.
Borgmann, Dmitri A.
Word Ways: Vol. 3
, Article 16.
Available at: http://digitalcommons.butler.edu/wordways/vol3/iss1/16