The Lattice Multiplication Algorithm

Aside from the standard multiplication algorithm we know, and the Line Multiplication which I already discussed, there is another method that we can use to multiply. This is called lattice multiplication. We can do this in multiplying 2-digit by 2-digit numbers but it can be extended to numbers with more digits. The steps of are as follows.

Step 1: Create 2 by 2 grid and place the numbers you want to multiply at the top and at the side as shown in the next figure. In this case, we want to multiply 83 by 42.

lattice multiplication

Step 2: Draw diagonals on each rectangle. This forms two triangles. These triangles will contain the digits of the product of the two given numbers. As shown below, the yellow square will contain the product of 3 and 2.  » Read more

An Explanation Why the Line Multiplication Trick Works

Mathematical concepts and operations can be represented in different ways. For example, a function can be represented using a table, set of ordered pairs, equations, or graphs. Another example is an equation which can also be represented as a balance.

In this post, we are going to discuss a representation of a simple concept which is very popular among netizens: multiplication of numbers using lines. Many are amazed about this representation that they even call it the magic line multiplication trick.

Note: If you don’t know the trick, watch first the video below. 

Now, let us learn why the line multiplication trick works.  » Read more