In our lesson, we learned a few valuable properties of addition. We identify the parts of an addition problem as either: sum or addend. The addends are the numbers being added together or combined through addition. The sum is the result of the addition operation. The commutative property of addition shows us that we can change the order of two or more addends without changing the sum. The associative property of addition shows us that we can change the grouping of three or more addends without changing the sum.

Test Objectives
• Demonstrate the ability to rewrite a sum using the commutative and associative properties
• Demonstrate the ability to identify the parts of an addition problem as addend or sum
• Demonstrate the ability to add using the identity property of zero

#1:

Instructions: Rewrite each using the commutative property.

a) 1 + 7

b) 2 + 4

c) 6 + 15

d) 13 + 12

#2:

Instructions: Rewrite each using the commutative property.

a) 21 + 1

b) 13 + 9

c) 51 + 7

d) 103 + 2

#3:

Instructions: Identify the parts of each addition problem.

a) 9 + 4 = 13

b) 12 + 10 = 22

c) 5 + 4 + 11 + 3 = 23

Instructions: Find each sum.

d) 37 + 0

e) 962 + 0

f) 1,362,373 + 0

#4:

Instructions: Rewrite each using the associative property.

a) (3 + 1) + 5

b) 17 + (11 + 2)

c) (9 + 2) + 1

#5:

Instructions: Rewrite each using the associative property.

a) (4 + 6) + 7

b) 13 + (2 + 8)

c) (10 + 20) + 15

Written Solutions:

#1:

Solutions:

a) 1 + 7 = 7 + 1

b) 2 + 4 = 4 + 2

c) 6 + 15 = 15 + 6

d) 13 + 12 = 12 + 13

#2:

Solutions:

a) 21 + 1 = 1 + 21

b) 13 + 9 = 9 + 13

c) 51 + 7 = 7 + 51

d) 103 + 2 = 2 + 103

#3:

Solutions:

d) 37 + 0 = 37

e) 962 + 0 = 962

f) 1,362,373 + 0 = 1,362,373

#4:

Solutions:

a) (3 + 1) + 5 = 3 + (1 + 5)

b) 17 + (11 + 2) = (17 + 11) + 2

c) (9 + 2) + 1 = 9 + (2 + 1)

#5:

Solutions:

a) (4 + 6) + 7 = 4 + (6 + 7)

b) 13 + (2 + 8) = (13 + 2) + 8

c) (10 + 20) + 15 = 10 + (20 + 15)