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**Monox D. I-Fly****Member**- Registered: 2015-12-02
- Posts: 860

Can an abacus (by abacus here I mean suanpan, the Chinese abacus) be used to do multiplication of two single digit numbers? Like 4 x 8, 7 x 5, 9 x 7, etc. I have been Googling around but all of them only show multiplication with either one or more number have more than one digit. One source even states that an abacus can't be used to multiply a single digit number with another single digit number and students must memorize the multiplication table to be able to multiply using abacus. This is weird to me, if abacus was built to make people count easier and it helps with addition, which is the simplest math operation, why to be able to multiply with abacus you have to memorize the multiplication table, in which multiplication is more complicated than addition?

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**David****Member**- From: Bumpkinland
- Registered: 2014-04-23
- Posts: 3,135

When I was in Chinese school, we started memorizing the timetable up to 12 x 12 at a very young age. If I remember correctly, the abacus is not meant to be used as a "calculator"... It lets you keep track of things.

Meaningless, meaningless, Everything is meaningless! - Ecclesiastes 1:2

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**mathaholic****Member**- From: Earth
- Registered: 2012-11-29
- Posts: 3,251

Well, I've tried some abacuses online and I had a hard time using it for multiplication So maybe not

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**Monox D. I-Fly****Member**- Registered: 2015-12-02
- Posts: 860

I have searched and found out that it could, by repeating the addition process manually...

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Lots of years ago we were also taught the multiplication table at a very early age.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Monox D. I-Fly****Member**- Registered: 2015-12-02
- Posts: 860

It's weird that those abacus users can memorize multiplication table but need an abacus to do a simple addition.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

I would think they use it for a bit more than simple addition.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**David****Member**- From: Bumpkinland
- Registered: 2014-04-23
- Posts: 3,135

Monox D. I-Fly wrote:

It's weird that those abacus users can memorize multiplication table but need an abacus to do a simple addition.

They use it to keep track of things. This is interesting... If you can read mandarin. http://baike.baidu.com/view/666642.htm

Meaningless, meaningless, Everything is meaningless! - Ecclesiastes 1:2

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**Monox D. I-Fly****Member**- Registered: 2015-12-02
- Posts: 860

David wrote:

Monox D. I-Fly wrote:They use it to keep track of things. This is interesting... If you can read mandarin. http://baike.baidu.com/view/666642.htm

I can't read Mandarin but I know some Kanjis. Why is there the word "heart" (心) in the title?

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

I can speak and understand a little Japanese, I can not read Mandarin. I have seen people calculate very quickly with an abacus.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**David****Member**- From: Bumpkinland
- Registered: 2014-04-23
- Posts: 3,135

珠心算 is the art of using abacus while calculating...

心算 is the art of calculating numbers your head without writing it down... (You count in your "heart")

An abacus is like the paper and the pencil combined together...

Meaningless, meaningless, Everything is meaningless! - Ecclesiastes 1:2

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**Monox D. I-Fly****Member**- Registered: 2015-12-02
- Posts: 860

bobbym wrote:

I can speak and understand a little Japanese, I can not read Mandarin. I have seen people calculate very quickly with an abacus.

Do you also know some Kanjis, ボッビーム?

David wrote:

珠心算 is the art of using abacus while calculating...

心算 is the art of calculating numbers your head without writing it down... (You count in your "heart")

What are the meanings of the other Chinese characters?

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Do you also know some Kanjis, ボッビーム?

I do not.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Monox D. I-Fly****Member**- Registered: 2015-12-02
- Posts: 860

mathaholic wrote:

Well, I've tried some abacuses online and I had a hard time using it for multiplication So maybe not

Can you multiple two numbers which both have two digits?

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

I do not know how to use an abacus, but in the old days they could beat guys with adding machines.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Monox D. I-Fly****Member**- Registered: 2015-12-02
- Posts: 860

Yes, I have read about it. By the way, can abacus be used to count divisions of two single digit numbers, for example, 8:2?

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

Watching this video I would say on a problem like that you would use mental division.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Monox D. I-Fly****Member**- Registered: 2015-12-02
- Posts: 860

I asked about a suanpan though, not a soroban.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Yes I know. I was hoping to find any abacus that could do what you requested.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Monox D. I-Fly****Member**- Registered: 2015-12-02
- Posts: 860

I gave up and just went with repeated subtraction.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Is this for a program?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Monox D. I-Fly****Member**- Registered: 2015-12-02
- Posts: 860

No. This time my boss asked me to write a book about abacus.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Okay, it does not seem to be able to.

The slide rule is like that, it can do lots of nice calculations but you have to place the decimal point!

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Monox D. I-Fly****Member**- Registered: 2015-12-02
- Posts: 860

This is harder than I imagined.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Is the Chinese one significantly different than the Soroban?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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