Area Model for Multiplication 4.NBT.5

In this lesson, you will multiply a 2-digit number by a 2-digit number using the area model strategy.

43 x 27 = ? 43 sets of 27 Smart estimate: 45 x 30 = 1,350

43 x 27 = ? Break apart the numbers by place values Draw a rectangle and label the dimensions Multiply Then add the parts 20 7 40 3 40 x 20 = 800 40 x 7 = 280 800 280 60 + 21 3 x 7 = 21 3 x 20 = 60 1,161

Try Another One: 34 x 45 Break apart the numbers by place values Draw a rectangle and label the dimensions Multiply Then add the parts 40 5 30 4 30 x 40 = 1200 30 x 5 = 150 1200 150 160 + 20 4 x 5 = 20 4 x 40 = 160 1,530

Do this one on your own: 26 x 78 Break apart the numbers by place values Draw a rectangle and label the dimensions Multiply Then add the parts 70 8 20 6 20 x 70 = 1400 20 x 8 = 160 1400 420 160 + 48 6 x 8 = 48 6 x 70 = 420 2,028 How did you do?

Area Model This method of multiplying supports students who are visual learners because they can easily see the “parts.” This method also supports student’s geometric knowledge of area. If you need more help, go to https://www.khanacademy.org/math/arithmetic/multiplication-division/area-models-multiplication/v/area-model-for-multiplication