In this activity, we'll find the perimeter of shapes by using the **measurements provided** to work out those that we're not given.

Perimeter is the distance around the outside of a shape.

Sounds a little tricky, but it's nice and easy. Let's have a look.

This shape has eight sides.

The lengths of six sides are provided.

We know that** opposite sides of a rectangle are equal.**

Even though it is not a rectangle, we can see that the lines along the top of the shape equal 7 m (5 + 2)

The lines across the bottom will also equal 7 m so the missing bottom length is 4 m (7 m - 3 m)

The lines down the left side equal 4 m (1 m + 3 m)

The lines down the right will also equal 4 m, so the missing length is 2 m (4 m - 2 m)

Now we have all the measures, we simply need to add them together.

**5 + 2 + 2 + 2 + 4 + 3 + 3 + 1 = 22 m**

We must remember to put the unit of measure, in this case, metres (m)

**Top Tip:**

It can help to mark each side as we add them.

This means we won't miss any out or count them twice!

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