Lattice Multiplication One option to solve multi-digit multiplication problems
This is the problem! 47 X 23 What do I do? I haven’t even learned my 12’s yet!
Let’s try using the Lattice Method First we need to draw a rectangle A square is a type of rectangle!!
Next we need to divide the rectangle into four squares (since there are four digits in the problem).
Now we need to add the numbers Now we need to add the numbers. The first number goes on top (one digit for each column); The second number goes on the right side (one digit for each row). 4 7 2 3
Now we add the diagonals (starting in upper right corner of each square). 4 7 2 3
Now, we get to do math . We need to multiply the digits and place the products in the boxes. The 10’s digit goes in the top half and the one’s go in the bottom half. If no digit put a zero in its place. 4 7 1 2 8 4 1 2 3 2 1
4 7 2 3 Now we add along the diagonals to get our answer. 1 8 1 1 8 4 1 1 2 1 8 4 1 2 3 2 1 8 1
4 7 2 3 Write the answer, use sums going counter clockwise. 1 8 1 1 2 1 8 4 1 2 3 2 1 8 1 47 X 23 = 1,081