I had bookmarked this a while back, but hadn’t really played with it. This is a visual method of multiplication using lines and intersections.
Cool, right! I love different thoughts about how to do math. Can you see how this one works? The lines crossing are basic multiplication, and then the design stacks the appropriate columns for tens, hundreds, etc. With very small numbers (4 or less) I can see how this might be easier, especially for people who do better with visuals then numbers, or perhaps someone like me who would prefer to count dots than remember multiplication tables. I never did learn most of those because I could do the math just as fast in my head. However, with large numbers it becomes tedious with too many points (which you might as well just multiply!).
Of course, thinking about multiplication this way, you could always just break numbers into their component parts for multiplying and it’s almost the same thing, right? For example, if I’m multiplying 4 by 52 (like, how many days a year I run approximately) I would multiply 4 by 50 and get 200 and then multiply 4 by 2 which is 8 and add them for 208. Same concept, but mental instead of visual.
Have you got any sneaky mental or visual tricks for complex multiplication?