The concept of **inverse operations** is an important one in mathematics. An inverse operation is an operation that undoes another operation. So what is the inverse of addition? multiplication?

A good way to develop our thinking about inverse operations is by filling in missing numbers as in the exercise below.

**Example**

**Exercise**

Let’s complete exercise 3 on pages 76 and 77 of the core textbook:

The answers are below:

**More challenging (and answer not given 😏)**

Find the value of * in the following calculation (it is a multiplication with missing digits. You do not have to use guesswork!

And here’s another one (this time I’ve put the answer afterwards, but don’t look at it until you’ve tried it):

**Answer**