## Key Concepts

- Count on the numbers
- Add numbers below 20
- Add numbers in any order
- Find the missing numbers

### Addition fact strategies

An equation uses an equal sign (=) to show that the value on the left is the same as the value on the right.

**Example 1:**

**Answer:**

6 + 3 = 9

3 + 6 = 9

→ 6 + 3 = 3 + 6 = 9

**Example 2:**

**Does 5 + 2 = 2 + 5? How do you know?**

**Answer: **

5 + 2 = 7

2 + 5 = 7

→ 5 + 2 = 2 + 5 = 7

### Addends

**You can change the order of the ****addends****.**

**Example 1:**

You can add numbers in any order, and the sum is the same.

So, 6 + 3 = 3 + 6.

You can write the facts this way, too

**Example 2:**

**Does 6 + 4 = 4 + 6? How do you know?**

**Answer: **

6 + 4 = 10

4 + 6 = 10

→ 6 + 4 = 4 + 6 = 10

### Find the missing numbers

**Example 1: **

**6 + ______ = 4 + 6**

**Answer:**

Here, we can observe equal sign which shows that the value on the left is the same as the value on the right.

4 + 6 = 10

And 6 + ___ = 10

→ 10 – 6 = 4

→ So, the missing number is 4

**Example 2:**

**8 + 2 = ____ + 8**

**Answer:**

Here, we can observe an equal sign which shows that the value on the left is the same as the value on the right.

8 + 2 = 10

And ___ + 8= 10

→ 10 – 8 = 2

→ So, the missing number is 2

**Example 3:**

**Add the numbers displayed on the top of the dice.**

**Answer:**

6 + 1 = 7

**Example 4:**

**Count the total number of apples and oranges. Find the total number of fruits.**

**Solution:**

Number of apples = 10

Number of oranges = 16

Total number of fruits = 10 + 16 = 26

## Exercise

- Count on to find the sum. Then change the order of the addends.

- Count on to find the sum. Then change the order of the addends.

- Count on to find the sum. Then change the order of the addends.

- Count on to find the sum. Then change the order of the addends.
- Count on to find the sum. Then change the order of the addends.

- Count on to find the sum. Then change the order of the addends.

- Count on to find the sum. Then change the order of the addends.

- Count on to find the sum. Then change the order of the addends.

- Find the missing numbers:

### Summary

- Counting on the greater number is easier.
- An equation uses an equal sign (=) to show that the value on the left is the same as the value on the right.
- You can change the order of the addends.

### Concept Map

### What have we learned

- Count on the numbers
- Add numbers below 20
- Add numbers in any order
- Find the missing numbers

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