MODULE 4 LESSON 7 Interpret area models to form rectangular arrays.

MODULE 4 LESSON 7Interpret area models to form rectangular arrays.

Skip countingLet’s skip count by 3s to 30.

36

9

1215

18

21

24

27

30

Skip countingLet’s skip count by 6s to 60.

612

18

2430

36

42

48

54

60

Skip countingLet’s skip count by 7s to 70.

714

21

2835

42

49

56

63

70

Skip countingLet’s skip count by 8s to 80.

816

24

3240

48

56

64

72

80

Skip countingLet’s skip count by 9s to 90.

918

27

3645

54

63

72

81

90

Draw Rectangles First of all, Make sure you have Grid Paper.

Draw a rectangle that has an area of 6 square units.

Draw a rectangle that has an area of 10 square units.

Draw a rectangle that has an area of 12 square units.

Draw a rectangle that has an area of 16 square units.

Draw a rectangle that has an area of 24 square units.

Draw a rectangle that has an area of 35 square units.

Thumbs up when you’re done!

Draw Rectangular Arrays

Draw a 4 x 2 rectangular array using the squares on your grid paper.

How many square units are in your array?

8 square units.

Draw Rectangular Arrays

Draw a 6 x 2 rectangular array using the squares on your grid paper.

How many square units are in your array?

12 square units.

Draw Rectangular Arrays

Draw a 4 x 3 rectangular array using the squares on your grid paper.

How many square units are in your array?

12 square units.

Draw Rectangular Arrays

Draw a 6 x 4 rectangular array using the squares on your grid paper.

How many square units are in your array?

24 square units.

Problem of the Day

Concept Development • Work with people at your table (you can have a group size

of 2 – 3)• Make sure each group has equal amounts of centimeter

tiles and square inch tiles. • Decide with your partner (group) how to arrange your tiles

to make the same shape rectangle. • Then create those rectangles with your pieces (cm cubes,

and square inch tiles)• Trace or draw a picture of your rectangles. • THUMBS UP WHEN YOU’RE FINISHED.

Time to think!• You and your partner(s) made the same shape rectangle.

Is there area also the same?• Why or why not?• Write the area of your rectangle on your board.• I will show you 1 square meter on the board• Suppose you used 12 square meter tiles to make your

rectangle. Would this rectangle have a BIGGER area or a smaller area compared to your rectangle?

• BIGGER

Still thinking…• Now I’m going to draw a square foot on the board. How

would your rectangle compare if you make it from 12 square feet?

•It would be bigger than 12 square inches or centimeters, but smaller than 12 square meters.

• How about this pad of sticky notes? • Still bigger than square inches or centimeters, but smaller than square feet or centimeters.

THE BIG QUESTION• Why is it important to label the UNIT when you’re talking

about area?• The area changes if the unit is small or big• If you do not know the unit then you really don’t know the

size of the area.

Relate area to multiplication to draw rectangular arrays• We will draw a rectangular array with an area of 18

square centimeters. • How might we find the side lengths? • Work with your partner to make a list of multiplication facts

that equal 18. • (1x18, 18x1, 2x9, 9x2, 3x6, 6x3)• Use a ruler to create a 3cm x 6cm rectangular array. • After drawing your squares, check your work by skip-

counting the rows to find the total number of tiles you drew.

• Thumbs up when you’re done.

3 cm

6 cm

3 cm

6 c

m

DOES THE RECTANGLE STILL HAVE THE SAME AREA?

• Erase the inside grid lines of your 3 x 6 rectangular array. • The empty rectangle with the labeled side lengths is

called the area model. How can you find the total area just using the labeled side lengths?

3cm

6 cm

What is the total area of this rectangle?

Suppose the unit In this area model is in inches.

The side lengths of thisModel are not labeled.

Do we need to drawgrid lines to find the area Of this rectangle?

What is the area of thisArea model?

8 square inches

PROBLEM SET!