Inverse operation to check answers

In this worksheet, children explore the inverse relationship

between addition and subtraction.

Addition and subtraction are inverse operations and addition is commutative and subtraction is not.

Bar models and part-whole models are useful representations

to help establish families of facts that can be found from one

calculation.

Children use inverse operations to check the accuracy

of their calculations, rather than simply redoing the same

calculation and potentially repeating the same error.

Ask:

What are the parts?

What is the whole?

Given one fact, what other facts can you write?

What does “inverse” mean?

What is the inverse of add/subtract