Systematic Treatise on Arithmetic (1592) - Page 3

For any multiplier from two to nine units, use this method: place the quantity of goods as the Dividend original: 實 (shí); the number being multiplied and the price as the Multiplier original: 法 (fǎ); the number acting upon the dividend. Recite the "nine-nine" The traditional Chinese multiplication table to combine the numbers. When the result is ten or more, place the "ten" digit at the current position original: 就身 (jiù shēn); a technical instruction for abacus carry-overs as if skipping a space. Begin calculating from the last digit. To restore the number to its original value, use the method of "nine-return" Division by a single digit.

The Verse for the Method of Multiplication

The Nine Multiplications must be memorized well	Start the calculation by pushing from the last digit
If the result is ten, place it at the current position as if skipping a place	If you wish to return to the original value, use the "nine-return" division method

General Song of Division and Multiplication

Division starts from the head The highest place value or "top" of the number	Multiplication is born from the foot The lowest place value or "bottom" of the number
When the rule says "as if," you must skip a place	When "speaking ten," the digit stays at the current position

Suppose there is now silver amounting to one hundred twenty-three taels and four mace. If each tael of silver buys 2 stones original: 石 (dàn); a unit of dry volume for grain of rice, the question is...