1. Use the distributive property to decompose units
Module 1 Lesson 19
Use the distributive property to decompose units
(Or, how to use easy math to solve hard problems)

2. Skip Count By 5s To 50 … (Robot)
Skip Count By 4s To 40 … (whisper)
Skip Count by 6s to 60 … (Russian)
Skip Count by 3s to 30 … (Operator)
Skip Count By 5s To 50 … (Robot)

3. COMMUTATIVE Multiplying
I will give you multiplication sentences. Use the commutative property to “Move It, Move It!” and give me an equivalent equation:
3 x 2 = x 2 = 10
2 x 3 = x 5 = 10
3 x 4 = x 8 = 16
4 x 3 = x 2 = 16
3 x 7 = x 3 = 15
7 x 3 = x 5 = 15

4. (5 fours) + ( _____ fours ) = 7 fours
Decompose & Multiply
In your math journal write the multiplication sentence for 7 fours:
7 x 4
Now write:
(5 fours) + ( _____ fours ) = 7 fours
What goes in the blank? 2

5. (5 fours) + ( 2 fours ) = 7 fours
Decompose & Multiply
(5 fours) + ( 2 fours ) = 7 fours =
= 28

6. (5 twos) + ( _____ twos ) = 8 twos
Let’s try it again!
In your math journal write the multiplication sentence for 8 twos:
8 x 2
Now write:
(5 twos) + ( _____ twos ) = 8 twos
What goes in the blank? 3

7. (5 twos) + ( 3 twos ) = 8 twos =
= 16

8. Problem of the Day ...
Henrietta works in a shoe store. She uses 2 shoelaces to lace each pair of shoes. Henrietta has a total of 24 shoelaces. How many pairs of shoes can Henrietta lace?

9. Henrietta can lace 12 pairs of shoes.
Problem of the Day ...
2 laces
24 laces
? pairs of shoes
Henrietta can lace 12 pairs of shoes. 2 4 6 8 10 12 14 16 18 20 22 24

10. Divide by Breaking Apart❂❂
24 ÷ 2 = ______
Let’s use the array to solve. Here is one way to break apart the array.
20 ÷ 2 = 10 and 4 ÷ 2 = 2
= 12

11. Divide by Breaking Apart
The twins are having a birthday party! They invite 27 people.
ALL THE PEOPLE ARE TRIPLETS!! One twin invited 15 people.
How many sets of triplets attended the birthday party?
How many triplets did each twin invite?

12. Concept Development 27 ÷ 3 = ? 15 ÷ 3 = 5 and 12 ÷ 3 = 4 5 + 4 = 9
❂❂❂
Let’s use an array to solve.
27 ÷ 3 = ?
15 ÷ 3 = 5 and 12 ÷ 3 = 4
5 + 4 = 9
9 SETS OF TRIPLETS ATTENDED THE PARTY.
One twin invited 5 sets; the other twin invited 4 sets.
27 ÷ 3 = 9

13. Problem Set: Show What You Know!