Inverse operation to check answers Foundation

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