Fact families

Key Notes:

  • A fact family is two addition number sentences and two subtraction number sentences that all use the same three numbers.

Learn with an example

❔What fact is missing from this fact family?

5 − 0 = 5
5 − 5 = 0
0 + 5 = 5 __________

  • This fact family has one addition number sentence and two subtraction number sentences. It is missing one addition number sentence.
  • The missing addition number sentence is the related addition fact for 0 + 5 = 5.
  • 5 + 0 = 5 is the missing fact.

❔What fact is missing from this fact family?

8 − 0 = 8
8 + 0 = 8
0 + 8 = 8__________

  • This fact family has two addition number sentences and one subtraction number sentence. It is missing one subtraction number sentence.
  • The missing subtraction number sentence is the related subtraction fact for 8 − 0 = 8.
  • 8 − 8 = 0 is the missing fact.

❔What fact is missing from this fact family?

7 − 7 = 0
0 + 7 = 7
7 − 0 = 7__________

  • This fact family has one addition number sentence and two subtraction number sentences. It is missing one addition number sentence.
  • The missing addition number sentence is the related addition fact for 0 + 7 = 7.
  • 7 + 0 = 7 is the missing fact.

Let’s practice!