<Li> 方 田 Fangtian - Bounding fields . Areas of fields of various shapes, such as rectangles, triangles, trapezoids, and circles; manipulation of vulgar fractions . Liu Hui's commentary includes a method for calculation of π and the approximate value of 3.14159 . </Li> <Li> 粟米 Sumi - Millet and rice . Exchange of commodities at different rates; unit pricing; the Rule of Three for solving proportions, using fractions . </Li> <Li> 衰 分 Cuifen - Proportional distribution . Distribution of commodities and money at proportional rates; deriving arithmetic and geometric sums . </Li> <Li> 少 廣 Shaoguang - Reducing dimensions . Finding the diameter or side of a shape given its volume or area . Division by mixed numbers; extraction of square and cube roots; diameter of sphere, perimeter and diameter of circle . </Li>

Who wrote the nine chapters on the mathematical art