2. RELATE ARRAYS TO TAPE DIAGRAMS TO MODEL THE COMMUTATIVE PROPERTY OF MULTIPLICATION. Module 1 Lesson 15

3. Multiply by Four 4 x 5 = ____ 4, 8, 12, 16, 20 4 x 5

4. Multiply by Four 4 x 3 = ______ 4 x 3 4, 8, 12

5. Multiply by 4 Pattern Sheet 2 minutes End

6. 4 inches = Length of 1 phone 4 inches = Length of 1 phone 9 Cell phones ? Length A cell phone is about 4 inches long. About how long are 9 cell phones laid end to end? Nine cell phones are 36 inches long.

7. CONCEPT DEVELOPMENT Fold you paper about 1/3 from the top. (look at teacher modeling) Draw an array with 2 rows and 4 columns ABOVE the fold on your paper. Use your array to show the commutative property of multiplication (hint: 2 x 4 = 4 x 2) Who remembers what the commutative property of multiplication is? The factors switch places, but the product stays the same.

8. 2 x 4 =8 4 x 2 = 8 Use the Commutative Property to write two multiplication equations for the array. Write them on the left side of the paper below the fold, one above the other.

9. 2 x 4 =8 4 x 2 = 8 * * * 8 2 Next to each equation, draw and label a tape diagram to match. Make sure the diagrams are the same size because they both represent the SAME total.. 8 4

10. LET’S TRY THIS AGAIN 5 x 4

11. X X X X X X X X X X X 4 x 5

12. Write two equations for this tape diagram. ✪✪✪✪✪✪✪✪ ✪✪✪✪✪✪✪✪ ✪✪✪✪✪✪✪✪ ✪✪✪✪✪✪✪✪ ✪✪✪✪✪✪✪✪ ✪✪✪✪✪✪✪✪ ✪✪✪✪✪✪✪✪ ✪✪✪✪✪✪✪✪ 7 x 4 = 28 4 x 7 = 28

13. Problem Set