Sunday, July 20, 2008

Multiplication using Vedic mathematics

I was sent this rather interesting video today. It claims to show how to multiply numbers with two and three digits. Probably the method will also work for numbers with four digits.



Since it is from Youtube, I have no idea if this is indeed Vedic mathematics or not. However, the trick used is very simple. What you do is use lines to represent numbers, and crossing lines represent multiplication - this is in fact a step back from the system we use. And it also takes more time that the methods for multiplication we are taught in school. Especially for numbers with a lot of digits....

2 comments:

(x, why?) said...

It's an interesting method. I've seen it in Mathematics Teacher magazine, but at this point the students either know it or they're reaching for the calculators.

Originally, I dismissed this as a curiosity, but it occurs to me that this could be used for multiple binomials. After all, that's technically what is being done when two two-digit numbers are being multiplied.

I don't expect them to keep doing it, but it might help the ones having trouble with FOIL make a little more sense out of it.

Anatoly said...

Hello (x, why),
Yes, it is a surprisingly straight forward method. I didn't try try timing myself, but I think that it is slower than doing the multiplication using modern numbers.

What is FOIL?