Nine Chapters on Mathematical Art, Vol. 1

Answer: 120 and 5/9 bu

There is another field, 18 and 5/7 bu wide and 23 and 6/11 bu long. Ask: What is the area of the field?

Answer: 1 mu a unit of land area, typically 240 square bu and 200 and 7/11 bu

Large Field Measurement

We, Chunfeng and others, respectfully note: Regarding the "Large Field Measurement," the initial method applies only to whole steps without remainder fractions. The secondary method applies only to remainders without whole steps. This method first observes the whole steps and then includes the remainders, which can encompass all three methods. Hence it is called Large Field Measurement.

Procedure: Let the denominator multiply each whole number, and add the numerator. Letting the denominator multiply each whole number and adding the numerator serves to convert the whole steps to include the numerator. Both the numerator and the denominator become the dividend. Multiply them to form the dividend, and multiply the denominators to form the divisor. Similar to multiplying fractions. Divide the dividend by the divisor. Now, because the method for width and length both have fractions, each must be converted individually.