In this worksheet, we will practice applying the associative property of addition of three numbers whose sum is, at most, 20.

**Q1: **

Find the missing number in .

Using that , what is ?

**Q3: **

Maged had 5 chocolate bars, 4 lollipops, and 3 gummy bears.

In total, he had candies.

Find another way to write the total number of candies.

- A
- B
- C
- D
- E

**Q4: **

Find the missing number in .

**Q5: **

We will see how we can write in different ways.

Find the missing number.

Find the missing number.

Complete the missing sum.

- A4, 8
- B7, 3
- C7, 6
- D11, 3
- E4, 9

All of these sums are equal. What are they equal to?

**Q6: **

When we add three numbers, we can first add any two of them.

For example, to find , we could first add 8 and 6 to get 14 as the picture shows.

Now, can you find the missing number?

**Q7: **

Find the missing number.

**Q8: **

Am I using the equal sign correctly? Check if the two sums are equal.

- A yes
- B no