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Abacus Math Program – Lesson 6 – Ten Pair Complement Addition Part 2

Continuing from Lesson 5, we will look at a few more 10 pair complement addition examples. Again there are 5 possible 10 pair complements: 9-1, 8-2, 7-3, 6-4, 5-5. All of these pairs can be used in two ways. For example we can use the pair 9-1 where we are trying to add 9 by subtracting the complement 1. But

Abacus Math Program – Lesson 5 – Ten Pair Complement Addition

In lesson 5, we will introduce the concept of 10 pair complements or 10 pairs. If you are new to abacus math, we suggest that you start from lesson 1. This abacus math lesson will use the 10 pair complement method for addition but as we will see in a later lesson the 10 pair complements are also

Abacus Math Program – Lesson 4 – Simple Multidigit Addition and Subtraction

With the basic abacus movements learned in the first 3 lessons on a single rod, we are now ready to apply our knowledge to more than 1 rod. If you have not looked at the first 3 lessons or are new to abacus math, I suggest you take a look at Lesson 1, Lesson 2, and Lesson 3 first which

Abacus Math Program – Lesson 3 – Simple Addition and Subtraction

In abacus math lesson 3 we are ready to look at combining numbers by adding and subtracting numbers within a single rod on the abacus or soroban. If you are not sure about how to enter or remove any of the digits 1 through 9 on the abacus, please take a look at abacus math lesson 1 for counting

Abacus Math Program – Lesson 2 – Counting 6 to 9

Now that we know how to enter and remove the numbers from 1 to 5 on the abacus, we will continue with the remaining numbers 6 to 9. From this point we will be able to represent all 10 digits, 0 through 9, on a single rod of the abacus or soroban. As a reminder, in

Abacus Basic Use and Introduction to Counting

This video is an introduction to soroban construction and some of its basic use.  Here we have a 17 rod soroban. I can represent a base-10 number up to 17 digits. The soroban is constructed with 17 vertical rods each rod containing 5 beads. The beads are separated by a counting bar call the reckoning

Abacus Math Program – Lesson 1 – Counting 1 to 5

Learning to use the abacus or soroban is learning to transform every arithmetic problem to a single digit operation similar to the four standard math algorithms taught in elementary school. By reducing problem complexity to just single digit operations, abacus users quickly gain both speed and accuracy. The RightLobeMath online abacus math program starts by teaching students 6 simple

How Many Beads are on an Abacus?

The answer to this question depends on the type of abacus you are considering. The Japanese version of the abacus, called a Soroban, has 5 beads per rod. Each rod of the Soroban can represent a digit from 0 to 9. Since a soroban is designed with a base-10 numbering system, the soroban is ideal

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January 2024
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1234567
891011121314
15161718192021
22232425262728
293031  
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  • General
  • SumoMath For Educators

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