2015-09-21 23:28:32

Hi, I have started using the abacus 1 row of 1 beads on top representing 5 and 4 on bottom representing 1. I know how to add and subtract but the thing I'm trying to do is multiply and divide. All the articles on the Internet are really confusing.

Bitcoin Address:
1MeNca7h6m8du4TV3psN4m4X666p6Y36u5m

2015-09-21 23:34:44

I actually have never used an abacus myself, but my lady uses one, I can ask her for you if you like.

With our dreaming and singing, Ceaseless and sorrowless we! The glory about us clinging Of the glorious futures we see,
Our souls with high music ringing; O men! It must ever be
That we dwell in our dreaming and singing, A little apart from ye. (Arthur O'Shaughnessy 1873.)

2015-09-22 00:18:25

I do not remember the multiplication and division rules for the abacus. sad
They always seemed kinda idiosyncratic and it was easier to just use one as scratch paper of a sort.

看過來!
"If you want utopia but reality gives you Lovecraft, you don't give up, you carve your utopia out of the corpses of dead gods."
MaxAngor wrote:
    George... Don't do that.

2015-09-22 01:54:05

@Dark that would be nice to know how. I heard its just a bunch of editions.

Bitcoin Address:
1MeNca7h6m8du4TV3psN4m4X666p6Y36u5m

2015-09-22 04:25:22

Okay. Multiplcation goes as follows.

Let's take the equasion 47x4 =

On one side, take the 47, let's put it on the left (It doesn't matter what side you use for multiplication). The four goes on the right, but not at the far edge. I was always taught to go the number of rows to the left that are in the equasion, so 4 7 times 4 (the times is part of the count) would be in what for addition would be the thousands column. So, on the far left is 47, and in the thousands column is the 4.

Now, You take 4 times 4, and that's sixteen, so to the right of the four (in the hundreds column, you put down the ten, and in the tens column you put the six).

Seven times four is twenty-eight, so in the tens column, where you put the six, add two more for twenty, and in the ones column add 8 for a total of 28.

Then clear the four out and you're done, leaving you with 188.

Division:

Let's use a different equasion because this one gets complicated if you don't have another abacus.

Let's use 320 divided by 5.

So 320 goes on the far right, and the five goes on the far left.

So, five goes into 3 0 times, so that doesn't work, so five goes into 32 six times because five times six is thirty.

Two colums to the left of the three, add six (I think of the spacing, like the first column is 0 and the second one is six, so again, the six is in the ten thousands column). Clear the three because five times six is thirty. So you're left with 20.

Five goes into twenty four times, so two to the left of the twenty, add four. Clear the two and you're done leaving you with a result of sixty-four.

I know this is kind of complicated, but hopefully it makes sense. I use a mental abacus for this kind of thing all the time.

thanks,
Michael

2015-09-22 10:16:15

Lol Drumbs, this reminds me why my marks in maths at school always varied hugely, sinse I always found that tht spacial representations with columns and numbers and what not made it far harder for me to come up with the answer, then again spacial awareness and representation is somethign I do not do well with.

It used to really piss off my maths teacher when he'd give us a complex problem and I'd just sit for two minutes and come up with a single right answer but could not show how I did it, I'd worked out both of your above somes but have no idea what your methodology means, maybe this is something I'll ask my lady to explain.

With our dreaming and singing, Ceaseless and sorrowless we! The glory about us clinging Of the glorious futures we see,
Our souls with high music ringing; O men! It must ever be
That we dwell in our dreaming and singing, A little apart from ye. (Arthur O'Shaughnessy 1873.)

2015-09-22 14:22:14

Yeah, the abacus is very spacial, and sometimes where you have to put things is kind of... interesting in regards to logic.

thanks,
Michael

2015-09-23 04:17:02

*Is thinking of Alice in Wonderland for some reason*

*Liked making the abacus look like the insides of castles from Super Mario Bros*

看過來!
"If you want utopia but reality gives you Lovecraft, you don't give up, you carve your utopia out of the corpses of dead gods."
MaxAngor wrote:
    George... Don't do that.

2015-09-23 07:57:20

Lol Key, well I did used to do that myself, my mum had an old abacus and making up mock Mario levels was mostly what I did with it, then again there was a point I would literally imagine most anything as if it were ledges in a 2D platformer big_smile.

With our dreaming and singing, Ceaseless and sorrowless we! The glory about us clinging Of the glorious futures we see,
Our souls with high music ringing; O men! It must ever be
That we dwell in our dreaming and singing, A little apart from ye. (Arthur O'Shaughnessy 1873.)