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The Answer is: 1,414 taels, 1 mace, and 4 candareens. The original units are Liang 兩, Qian 錢, and Fen 分. In this system, 10 candareens equal 1 mace, and 10 mace equal 1 tael.
The Method states: Set the quantity of timber as the Multiplicand (Shi 實). Use the price of 6 candareens per log as the Multiplier (Fa 法). Multiply them together to satisfy the question.
| End of the Multiplicand | Start of the Multiplicand | ||||
|---|---|---|---|---|---|
| Units | Tens | Hundreds | Thousands | Ten-Thousands | |
| Start by calling 6 | 6 times 6 | 6 times 5 | 6 times 3 | 6 times 2 | |
| Fifty-four | Thirty-six | Results in thirty | Eighteen | Twelve | |
| Change 9 to 5 | Change 6 to 3 | Change 5 to 3 | Change 3 to 1 | Change 2 to 1 | |
| Add 4 to the position below | Add 6 to the position below | Add 8 to the position below | Add 2 to the position below | ||
| Determining the Place Value | Original Multiplicand | ||||
| Units | Tens | Hundreds | Thousands | Ten-Thousands | |
| These are candareens; move forward and ascend to find the result | Above the multiplier is 6 candareens per log; where the logs end, stop; the next position below is the candareens place | Start by calling "Ten-Thousand" at the end | |||
| ❹ | Mace | Tens | Hundreds | Thousands | Ten-Thousands |
| Count in order down to the individual logs | |||||
| 5 |
The table above illustrates the "Yin" (multiplication) method using a counting board or abacus. The "Change X to Y" instructions describe how to manipulate the beads or rods to reflect the products of the multiplication table (e.g., 6 x 2 = 12 is handled by changing the digit 2 to 1 and adding 2 to the next lower position).
General Source of Computational Methods original: "Suanfa Tongzong" 算法統宗, a seminal 16th-century mathematical treatise by Cheng Dawei. Volume 11