If you’re anything like me, you may have forgotten how to do many types of mathematical equations without resorting to Google or a calculator app, though having a trick up your sleeve to do so can come in handy sometimes.
This method we unearthed back in 2013 is a handy visual guide to large multiplications — and while it may not be faster than other methods floating around out there, it’s a great way for visual learners to work out multiplications that involve large numbers.
The method is demonstrated in the video above, but here’s the basic gist of it: You draw diagonal lines to represent the numbers in the sum. Ie, 223 x 131 would be a group of two, two and three lines, crossed by a group of one, three and one lines. Once all the lines are drawn, you just separate the diagram into vertical slices and count up the number of intersecting lines in each slice.
While it’s probably not the quickest way to get your answer, it is a method that is really easy to remember — and I know I’ll be keeping it in mind for the future. At least until we get some kind of embeddable chip that automatically calculates anything in response to a brain signal. It probably won’t be long.
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