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How to multiply numbers by drawing lines

Learn how drawing lines and counting can visually calculate multi-digit multiplication problems. This handy math trick, sometimes referred to as the Japanese Multiplication Trick, lets little kids, visual learners, and math enthusiasts of all ages easily figure out 58×34, 753×691, and more by drawing diagonal lines, counting the intersections, and then assembling the totals. Presh Talwalkar of Mind Your Decisions created the helpful video above.

Why does this work? Talwalker has a thorough video for that, too:

Related listening with But Why? A Podcast for Curious Kids: What’s the Biggest Number?

Next, more math videos, including the mathematical secrets of Pascal’s triangle and How high can you count on your fingers?

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