Fact Families

Related addition (subtraction) facts are the facts that use the same numbers.

For example: Consider the subtraction sentence.

4 – 1 = 3

Let's write the related subtraction fact for the given subtraction sentence.

4 – 1 = 3

We have:

From above, we can also say that:
 

4 – 3 = 1
 

So, the related subtraction fact for the given fact is 4 – 3 = 1.