Commutative Property of Addition Worksheets with Answer Key - Free Printable

Let's solve this Commutative Property of Addition Worksheet step by step.

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🔍 What is the Commutative Property of Addition?

The commutative property of addition states that:
> Changing the order of the addends does not change the sum.

In other words:
> $ a + b = b + a $

So, if we have an equation like:
> $ 10 + 5 = 5 + \boxed{10} $

We just switch the two numbers being added.

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Now let’s go through each problem and fill in the blanks using this rule.

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✔ Solutions:

#### 1. $ 16 + 6 = 6 + \boxed{16} $
Switch 16 and 6 → $ 6 + 16 $

#### 2. $ 11 + 4 = \boxed{4} + 11 $
Switch 11 and 4 → $ 4 + 11 $

#### 3. $ 6 + 8 = \boxed{8} + 6 $
Switch 6 and 8 → $ 8 + 6 $

#### 4. $ 7 + 9 = \boxed{9} + 7 $
Switch 7 and 9 → $ 9 + 7 $

#### 5. $ 2 + \boxed{3} = 3 + 2 $
Switch 2 and 3 → $ 3 + 2 $, so missing number is 3

#### 6. $ 9 + \boxed{10} = 10 + 9 $
Switch 9 and 10 → $ 10 + 9 $, so missing number is 10

#### 7. $ 4 + \boxed{5} = 5 + 4 $
Switch 4 and 5 → $ 5 + 4 $, so missing number is 5

#### 8. $ 11 + \boxed{7} = 7 + 11 $
Switch 11 and 7 → $ 7 + 11 $, so missing number is 7

#### 9. $ 12 + 9 = \boxed{9} + 12 $
Switch 12 and 9 → $ 9 + 12 $

#### 10. $ 13 + \boxed{5} = 5 + 13 $
Switch 13 and 5 → $ 5 + 13 $, so missing number is 5

#### 11. $ 14 + \boxed{3} = 3 + 14 $
Switch 14 and 3 → $ 3 + 14 $, so missing number is 3

#### 12. $ 8 + 16 = \boxed{16} + 8 $
Switch 8 and 16 → $ 16 + 8 $

#### 13. $ 6 + \boxed{7} = 7 + 6 $
Switch 6 and 7 → $ 7 + 6 $, so missing number is 7

#### 14. $ 8 + 12 = \boxed{12} + 8 $
Switch 8 and 12 → $ 12 + 8 $

#### 15. $ 13 + 12 = 12 + \boxed{13} $
Switch 13 and 12 → $ 12 + 13 $

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✔ Final Answers:

| Problem | Answer |
|--------|--------|
| 1 | 16 |
| 2 | 4 |
| 3 | 8 |
| 4 | 9 |
| 5 | 3 |
| 6 | 10 |
| 7 | 5 |
| 8 | 7 |
| 9 | 9 |
| 10 | 5 |
| 11 | 3 |
| 12 | 16 |
| 13 | 7 |
| 14 | 12 |
| 15 | 13 |

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📝 Summary:

All problems are based on switching the order of addends. The commutative property tells us that the sum stays the same regardless of order.

✔ So, whenever you see $ a + b = ? + a $, the missing number is b.

This worksheet reinforces understanding that addition is commutative — order doesn’t matter!

Let me know if you'd like this as a printable PDF or with explanations for kids!