Lattice Multiplication is an alternative way of doing higher level multiplication.

By creating a series of grids (boxes) and following a few rules you can easily and neatly find the product to large numbers.

Today’s Example: 64 x 9 =

First, write the larger number down.

6 4

Draw a rectangle below this number.

6 4

The larger number is made up of 2 digits, so cut the rectangle into two boxes.

6 4

Write the other problem number on the right of the rectangle.

6 4 9

Cut the boxes diagonally. For each box draw a line from the bottom left to the top right.

6 4 9

Now we do basic multiplication. Start with the 6. If we go down from the 6 and across from the 9 they “meet” in that first box.

6 4 9

6 x 9 = 5 4 Write 5 in the top half of the box and write 4 in the bottom half of the box.

Move on to the 4. If we go down from the 4 and across from the 9 they “meet” in that second box.

4 x 9 = 3 6 Write 3 in the top half of the box and write 6 in the bottom half of the box.

Extend your diagonal lines down.

Add the numbers inside the boxes. Use the diagonal lines to guide you. Start on the right with the 6 then move to the left. 6 + nothing = 6. So put a 6 on the right of the diagonal lines.

3 + 4 = 7. So put a 7 between the diagonal lines.

5 + nothing = 5. So put a 5 to the left of the diagonal lines.

That’s it! 576 is your answer. 6 4 x 9 = 5 7 6

ON YOUR OWN Try the following problem using the rules from the example. The answer will be the first thing given in TUTORIAL 2.

On Your Own Problem: 52 x 7 =