Fact families

What is a fact family?

Fact families are groups of number sentences that use the same three numbers.

Using any two of those numbers you can use addition or subtraction to find the third.

For example, you can make the following fact family using the numbers 2, 4 and 6:

Activity: What are fact families?

Complete the interactivity to learn more about fact families and then put your knowledge to the test.

Fact families

Fact families are groups of numbers that have a relationship to each other.

For each pair of addition facts, there are also two subtraction facts in the same family.

Here is a fact family using the numbers 3, 4 and 7.

All of these number facts use the equals sign (=).

With addition, it doesn't matter which order you add things, the total is the same.

In this example, the addition facts are:

3 + 4 = 7

4 + 3 = 7

The subtraction facts are:

7 - 4 = 3

7 - 3 = 4