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.
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