# Common core addition

## Common core addition - Line addition (or open number line)

This is a method of adding two numbers using small progressive steps along a line.

**Example 1**

`42+27`

To see how this is broken down

## Step by step

**Example 1**

`42+27`

**Answer:** `=69`

**Answer:** `=69`

**Example 2**

`419+275`

To see how this is broken down

## Step by step

**Example 2**

`419+275`

**Answer:** `=964`

**Example 3**

`256+137`

To see how this is broken down

## Step by step

**Example 3**

`256+137`

**Answer:** `256+137=393`

**Answer:** `=393`