In this activity, we're going to be converting between **metres, centimetres and millimetres.**

**Information that will help us:**

There are 100 cm in a m

There are 10 mm in a cm

mm = millimetre

cm = centimetre

m = metre

When we **multiply** by 10, all the digits move one place to the **left **(the decimal point does not move)

When we** divide** by 10, all the digits move one place to the **right** (the decimal point does not move)

When we **multiply** by 100, all the digits move two places to the **left **(the decimal point does not move)

When we** divide** by 100, all the digits move two places to the **right** (the decimal point does not move)

We can use the information above to help us answer the questions in this activity.

It is useful to **learn this information** and keep it in your head!

For this activity, you can look back at this information by clicking on the red help button on the screen.

**Let's have a look at an example:**

How many mm are there in 32 cm?

We know that there are 10 mm in 1 cm

To convert 32 cm into mm we need to multiply 32 by 10

32 x 10 = 320 mm

**32 cm = 320 mm**

Now let's look at another question - this time as a word problem:

A book is **15 cm** in length.

What is the total length of** 2 **books in **mm?**

First, we need to find the total length of the books.

2 x 15 cm = 30 cm

Now, we convert 30 cm to millimetres.

30 x 10 = 300

**The total length is 300 mm**

Now, why don't you have a go at some questions?