In **subtraction**, you take something away. (It is the opposite of **addition**. In addtion, you add something on.)

**Example**

Look at this problem. A number is missing.

You need to find its value.

6 | + | ? |
= | 17 |

**Answer**

You can use subtraction. Here's how.

17 - 6 = 11

So the missing number is = 11

Check your answer:

6 + 11 = 17