Lattice Math

Math Monday

Multiplication Strategies

There are several multiplication strategies: arrays, equal groups, repeated addition, skip counting, and fact families as viewed in the image on the right. As students progress to multiplying larger numbers with two, three digits or more, another method to use is Lattice Math. This method dates back to the 13th Century.

Let's multiply 216 X 32 using Lattice Math (also called Shabakh, Venetian Squares, Chinese Lattice) as seen in the image below.

Lattice Math method

For multiplying this three digit number by a two digit number using the Lattice algorithm: draw a box with a grid of  three vertical columns and two horizontal columns. Place the number 216 across the top of the box. Place the number 32 along the right side of the box.

Next, draw a vertical line from the bottom left corner to the top right corner of each box to divide the tens from the ones. This will split each box diagonally. As we multiply, the tens will go on top left of the vertical line while the ones will go in the bottom right side of each box.

Starting at the right side of the box, multiply 3 X 2 and place the six in the first box on the left under the 2. With the answer of 6 there is not a ten so place a zero in the upper left side and a six in the lower right side of the box. Continue to the next box to the right and place the answer for 3 X 1.

Continue until all the boxes are filled. The answer is seen in green and read along side the box beginning at the upper left.

216 X 32 = 6, 912.

From E-How Education, here is a video explanation for using  Lattice Math to solve 14 X 56:

For additional practice with multiplying two digit numbers, here is a free template from Teacher Vault:

For additional practice multiplying 3 digit numbers, here is free template from Math Worksheets 4 Kids:

For accommodating students who need additional support, use a multiplication table print out such as this one:

Multiplication Table printable

Thank you for visiting, Tricia