This Multiplication Line Technique is Mind-Blowing.

Once you have finished secondary school, there's not much to multiply by hand. We all have supercomputers in our pockets to math for us, not having to take a scratch paper or your handy multiplication tables. However, we've just learned about a technique of multiplication that not only exciting to do at hand but also mind-blowing.

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Draw Your Work

You know how to multiply by the side, right? First, you put the two figures upside down. Then the top numbers are multiplied by the numbers below them, and then the numbers below them are multiplied by the digit below (make sure that you add 0 to end), and then the top numbers multiplied by the digit in the center below, and so on. Finally, add all the digits and voila, you have your reply. Well, if it just makes you feel bored. Fortunately, there is another way of doing it with a drawing technique.

Let's begin with a simple one. Say you want to multiply 2 and 13. Draw first, from lower left and to top right, 2 parallel diagonal rows. Draw the next 13 further diagonal lines perpendicular to (and cross-sectioning) the first one, this time from the top-left and going to the bottom-right. (Each subsequent line is to place to the right of the last one.) Formulate the crossroads dots. You ought to get 26—and your answer is there. It's a no-brainer! Let's now add two-digit combinations to the paper.

We're going to do 31x 22. For the 31, draw from the lower-left three diagonal lines, leave a room and then another diagonal line. Do the same for the 22— two upper-left lines, space and then two additional lines. The results are in a diamond with three rows on the top right, two on the bottom left, a line on the bottom right and two rows on the top right.

After that, try to imagine the vertical segment of the diamond. The upper and lower corners are in one section because they are vertically aligned, and the right corner is all alone, like the left corner. Now you add the crossroads again. The leftmost segment should be 6, the center section should be eight, and the right side should be 2. Voila! Your result is 682.

Scaling Up

A pretty amazing method, right? Our minds have really blown away to see it happen. However, fun is right in front of you. Let's try the numbers 31 and 23 again. There's only one distinct number, but an interesting wrinkle adds. This moment you will have a six at the bottom, an eleven at the center and a third at the bottom. That is the eleventh point of the issue. You'll have to perform the one, just like more well-known multiplications, to add it to the six of the left hand and your result is 713.

The same procedure operates on three digits too, but the steps must not take. To solve the problem 49,852 multiply 412 by 121 using the technique and arrange it again in those vertical rows — you'll get 4, 9, 8, 5 and 2.

Try another scenario. Let's attempt one more. Let's have 246 and 305 multiplying. You know the drill. Start from two lines then from four to six. Do three lines now, then... Null lines?)(Five lines, then. Indeed, one row in a distinct color to depth the 0, and make a mental note not to count junctions that include that color, is actually the best way to ensure it's correct. You're going to get 6, 12, 28, 20 and 30 for this issue. This is a lot to figures, but the end outcome is 75,030. That's undoubtedly magic you know.

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