Friday, October 22, 2010

Have You Got A Soroban?

We have a new toy in the house. I bought it for Aaron but like so many other things, I think I'm the one that is having all the fun.

Check out our new Soroban ...

A Soroban is actually the Japanese derivation of the Chinese abacus, the Suanpan. I bought the abacus on ebay and actually thought it was a Taiwanese type until I turned to trusty Google to learn how to use one. So, official information now is that the one we own is the Japanese type, referred to as the Soroban. It has one top bead and one bottom bead less than the Chinese one.

I think I got my information mixed up. They do a lot of abacus training in Taiwan but don't actually have their own type of abacus. Where did I hear this from? An eleven year old boy who can do addition, subtraction, division OR multiplication in his head as fast as I can with the calculator.

Five years ago, I taught piano to the most serious eleven year old boy you can imagine. He was the perfect piano student. And then, I found out that he was super with his mental sums. His skills fascinated me and I spent a lot of time competing with him - my calculator against his brain. It was truly amazing. We're not talking about simple two digit operations here. I could give him numbers in the tens of thousands to work with and he would still match my calculator. Can't remember if we went to hundreds of thousands or not. It turns out that he got that good by first training with the abacus. After a few years, he must have developed an abacus in his head that he could manipulate.

I'm not trying to turn Aaron into a math whiz. I just thought this would be a fun way for us to play around with numbers. We've been using cards, and dice and now, the Soroban will be another visual aid for numbers.

I've been playing around a lot with the one that we've got and even though I'm slow, I can see how its use can match a calculator. You can play around with this virtual Soroban to see how the numbers will look like. The first rod on the right is the unit rod, the next is tens, then hundreds, thousands, etc. Go have a look by keying in the digits. Make sure you look at what 5 is because its the pivot point for counting to 10.

If you've taken a look at how to count and if you've got the spare time and are interested, this is how simple addition can be.

112 + 232 = 344

To make 112, start with the third rod from the right. Push 1 bead up. Then, push 1 bead up on the next rod and 2 on the last rod.

Then, starting with the third rod from the right (the one where you should have one bead):
- push 2 beads up
- move to the next rod, push 3 beads up
- move to the next (and last) rod, push 2 beads up.

Now, when you look at the last three rods of the Soroban, you'll have 3, 4 and 4 beads. And thats the answer.

Have I confused you all? Can you see how it can be fun? Imagine the speed that you could get on this thing once you've practiced. (Yes, I know we have calculators these days but I believe this will train your brain to eventually do the math without the actual Soroban) Go get a real one and play around with it. Makes a nice clicking sound when you can go fast.


Mike said...

I've been banned from Soro for a long time now. I didn't think anyone would ever find out.

Bilbo said...

I think I blogged one time about the $98 I spent in 1973 on a top-of-the-line calculator (add, subtract, multiply, divide, change signs, no memory) that was hopelessly outclassed by the slide rule. I also have a great cartoon in my collection that shows a group of scientists gathered in front of an enormous computer - beside the computer is a sign reading "In Case of Emergency, Break Glass," and behind the glass is ... an abacus!

Jean-Luc Picard said...

This looksd a lot more interesting than an abacus.