The English measuring system classifies the measurement of cups in only 10 sizes: 1/4 cup, 1/3, 1/2, 2/3, 3/4, 1, 1 1/4, 1 1/2, 1 3/4, 2. This is because the scale that the international metric system and the English system agreed was only for these sizes due to the closed tens and hundreds goal. It is easier to make conversions from one system to the other, instead of smaller sizes that would require less closed conversions.
