Understanding Area Models for Multiplication. Making Sense of Multiplication Using any of the tools available at your table: Model 3 x 4.

Understanding Area Models for Multiplication

Understanding Area Models for Multiplication

Making Sense of Multiplication

Using any of the tools available at your table:

• Model 3 x 4

Meanings for multiplication

Repeated addition xxxx xxxx xxxx Array

xxxx

xxxx

xxxx Area Counting possibilities (I have 3 shirts and 2

pants, how many outfits?)3

With materials at your table, use an area model to show:

6 x 13

Using an area model to calculate 6 x 13:13

6

6 x 13 = 78

Making Sense of Multiplication

Using an area model to calculate 6 x 13:

10 3

6 6 x 10 6 x3

6 x 13 = 6 x (10 + 3) = (6 x 10) + (6 x 3) = 60 + 18 = 78

Making Sense of Multiplication

With materials at your table, use an area model to show:

12 x 26

Using an area model to calculate 12 x 26:

20 6

10

2

10 x 20 10x 6

2 x 20 2 x 6

Making Sense of Multiplication

12 x 26 = (10 + 2) (20 + 6) =

(10 x 20) + (10 x 6) + (2 x 20) + (2 x 6) =

200 + 60 + 40 + 12 = 312

9

Mixed Number Multiplication

How would you solve 2

1

4ÊÊ3

1

2?

Using a ruler and card, draw a rectangle that is by

inches, and find the total number of square inches.

Find your answer first by counting, then by multiplying.

Compare your answers--are they the same?

2

1

4

3

1

2

10

Mixed Number Multiplication

2

1

4ÊÊ3

1

2(2ÊÊ

1

4Ê)(3ÊÊ

1

2)

2

1

4

3

1

2

11

Mixed Number Multiplication

2

1

4ÊÊ3

1

2(2ÊÊ

1

4Ê)(3ÊÊ

1

2)

2

1

4

3

1

2

Area model for fractionsfractionareamodel.gsp

12

1

2

1

3

A decimal example:

13