Email or username:

Password:

Forgot your password?
Devine Lu Linvega's posts Post Back to profile
Top-level
Devine Lu Linvega

I'm not sure if you're familiar with this visual way of multiplying numbers together, it has nothing to do with fractions, but I just thought about it. I think it's called vedic multiplication sometimes, or just the sticks method.

I'm using a thicker line here to represent 4 to save me some time, so intersections with the thicker line are worth 4, two thick intersecting lines would be worth 16.

20 Jul 2022 at 3:56 | Open on merveilles.town
3 comments
max22-

@neauoire it reminds me a little technique i had found somewhere (but i don't remember where) when i was at school, to multiply 2 polynomials. You put the coefficients on lines and columns of a table, you multiply them in each cell, and you add the diagonals to obtain the result. It looks like we can do it with your technique too, except you have to invent a way to deal with negative numbers ☺️
20 Jul 2022 at 8:30 | Open on mastodon.xyz
Devine Lu Linvega

@maxime_andre ah yes! I have this one on my wiki, it's called the peasant method sometimes.

20 Jul 2022 at 14:58 | Open on merveilles.town
Stewart Russell

@neauoire @maxime_andre I thought this (below) was known as peasant multiplication? You double one number and half the other, and only add the "doubles" where the "halfs" are odd numbers.

Yes, it's simple binary shift and add multiplication, as used on very simple computers

X 34 12 X X 68 6 X 136 3 272 1 34 × 12 = 136 + 272 = 408
20 Jul 2022 at 20:54 | Open on mastodon.social
Go Up