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Methods: There are many methods to perform multiplication with the Chinese Abacus. Below is one of the simpler methods. In the future, I will add an advanced topic on the methods of multiplication and division. Because performing multiplication requires more space, after you learn this method you should use the Cyber Chinese Abacus to practice rather than using the small Abacus on this page.

One Column Seperation Method (OCSM):

(One Digit Multiplication) -- Positions of Multiplicand - Start the highest digit of the multiplicand in the far left column then move to the right. (I chose to start from the far left column because it is easier to demonstrate. Once you have learned the method, you can pick any column you like.) Unlike some other methods, we don't place the multiplier on the Abacus using the OCSM. We just keep it in our memory during the multiplication process. But, as a beginner, you can put the multiplier on the far right side of the Abacus for convenience. After you are famililar with the process, you don't need to do this. Direction & Sequence - the multiplication starts from the lowest digit of the multiplicand and one by one is multiplied by the multiplier and ends with the highest digit. The digit that was just multiplied by the multiplier will be removed one by one after the multiplication. Position of Product - it will be accumulated to the following two columns right after the multiplicand digit that was just multiplied by the multiplier. It's confusing, right? O.K., let's explain by doing an example 789 x 4 = ?. For easy reference, we named the Abacus columns from left to right as A, B, C, D, E, F, G, H, I, and J. You should follow the following instructions to practice. We set figure 789 in columns A, B and C , then set 4 in column J (option). First we multiply 9 in column C by 4 and add the product 36 by putting digit 3 in column D and digit 6 in column E (the two columns to the right of 9). Then get rid of 9 in column C. Thus, we always have one empty column to seperate the rest of the mutiplicand and the product (that is why we name it OCSM). Then, we multipy 8 in column B by 4 and add the product 32 by digit 3 in column C and digit 2 in column D. Then get rid of the 8 in column B. Now the figure in C, D, and E should be 3, 5, and 6. Finally, we multipy 7 in column A by 4 and add the product 28 to digit 2 in column B and digit 8 in column C. Then get rid of 7 in the column A. Now the figure in B, C, D, and E should be 3, 1, 5, and 6. We got it! The product of 789 x 4 is 3156. Now let's do the convertion. Convert the example to 4 x 789. First set 4 (multiplicand) in column A, and multipy 4 with the 7, the 100-digit of the multiplier, and add the product 28 in column B and C. Then multipy 4 with the 8, the 10-digit of the multiplier, and add the product 32 in column C and D (now the product goes in the opposite direction). Now the figure in columns B, C, and D should be 3, 1, 2. Finally, multiply 4 with the unit-digit 9 of the multiplier and add the product 36 in columns D and E, and get rid of the 4 (multiplicand) in column A. Now the figure in columns B, C, D and E should be 3, 1, 5, and 6, the same as the original example. Now is the right time to remind you about one important thing. The product of 2 figures always has 2 digits, e.g., the product of 3x3 should be 09 instead of only 9. When we do the multi-digit figures multiplication this rule is important.

(Multi Digits Multiplication) -- Positions of Multiplicand - same as the mono digit multiplication. Direction & Sequence - starts from the lowest digit of the multiplicand, multipied by multiplier from its highest digit to the lowest digit one by one, for example, 4x789. Position of Product - same as the example 4 x 789. Let's do one more example to explain, e.g., 703 x 843 = ? I think we had better to do this example with the Cyber Chinese Abacus. Go to next page.