Math Unit 3 Lesson 6 Use the distributive property to multiply and divide using units of 6 and 7.

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Multiply by 6! 6 x 7 = n Skip count by 6 to find the answer. Start from 30! Skip count by 6 to find the answer. This time, start from 60 and count backwards! 42 How do we write the answer when the problem uses a letter (or VARIABLE)? n = 42

Transcript of Math Unit 3 Lesson 6 Use the distributive property to multiply and divide using units of 6 and 7.

4251 30011 0010 1010 1101 0001 0100 1011

Math Unit 3 Lesson 6

Use the distributive propertyto multiply and divide using units of 6 and 7.

Multiply by 6!6 x 7 = n

Skip count by 6 to find the answer.Start from 30!

Skip count by 6 to find the answer.This time, start from 60 and count backwards!

42 How do we write the answer when the problem uses a letter (or VARIABLE)?

n = 42

Now you try it …6 x 9 = n

Right side of the room skip count up from 30.Left side count down from 60.Put your hand on your head when you have the answer!

54 n = 54

Now you try it …6 x 6 = n

Left side of the room skip count up from 30.Right side count down from 60.Put your finger on your nose when you have the answer!

36 n = 36

Now you try it …6 x 8 = n

Front of the room skip count up from 30.Back side count down from 60.Put your hand on your shoulder when you have the answer!

48 n = 48

Skip Count By 7s To 70 … 7 14 21 28 35 42 49 56 63 70

Skip Count by 8s to 80 … 8 16 24 32 40 48 56 64 72 80

Skip Count by 9s to 90 … 9 18 27 36 45 54 63 72 81 90

Skip Count

Problem of the DayDakota cuts a long piece of ribbon into 9 pieces to make Christmas ornaments. Each piece she cuts is 7 cm long. How long was Dakota’s original piece of ribbon?

9 pieces = r cm

7 cm

Solution of the DayDakota cuts a long piece of ribbon into 9 pieces to make Christmas ornaments. Each piece she cuts is 7 cm long. How long was Dakota’s original piece of ribbon?

9 pieces = r cm

7 77

9 X 7 = r

7 777 7 7

9 X 7 = r r = 63 cm

Distributive PropertyDistributive Property says that multiplying a number by a group of numbers added together is the same as doing each multiplication separately.

Example: 7 x 9 = 7 × (5 + 4) = (7×5) + (7×4)

So the “7" can be "distributed" across the “5+4" into “7 x 5” and “7 x 4.”

Think of the Distributive Property asthe LEGO property! “Distributive”means you can take apart a hardmath problem and put it backtogether in a way that is easierfor you to solve.

Distributive Property Examples

48

12

36

Distributive Property Examples

54

24

30

Distributive Property Examples

49

14

35

Distributive Property Examples

63

21

42

Apply the Distributive PropertyWhat multiplication fact did we use to

solve the problem of the day?

9 x 7!Let’s write that problem in unit form:

9 sevensOn your white board, draw a tape diagram showing 9 x 7. Write the multiplication fact under it.

Apply the Distributive Property

7 7 7 7 7 7 7 7 7

9 x 75 x 7

Let’s use the distributive property to break this multiplication fact into two smaller facts that might be easier to solve.

4 x 735+ 28= 63

Use the Distributive Property to Divide

We can also use the Distributive Property to divide. In Unit One, we used arrays to do this. We took one large array and divided it into two smaller arrays:

18 ÷ 3 = [6 ÷ 3] + [12 ÷ 3]

Distributive Property Examples

48 ÷ 6

30 ÷ 6 18 ÷ 6

Today, let’s use a number bond to divide:

5 3

8

Now let’s write the math sentences we just used to solve this division fact:

48÷ 6 = (30 ÷ 6) + (18 ÷ 6) = 5 + 3 = 8

Time for the Problem Set!