The** capacity **of something is the amount it can hold.

We could talk about the capacity of a thimble, a cup, a bottle or even a swimming pool!

In this activity, we're going to look at a range of containers and estimate how much is in them, or how much they can hold in total.

We often describe a container as being full, half full or empty.

If we want an accurate measure, we can calculate capacity in millilitres (ml) or litres (l).

There are 1,000 ml in 1 litre.

Usually, a can of cola holds 330 ml (you can use this as a guide when answering some of the questions).

Let's have a look at an example:

How much liquid is in this jug?

We can see that the unit of measure is ml.

The line on the jug is level with 200 ml.

There are 200 ml of liquid in the jug.

We could also describe the jug as being approximately half full.

What is the total capacity of the jug?

We need to look at the top number on the scale.

This number is 400

The total capacity of the jug is 400 ml

Which jug has the greatest capacity?

We need to look at how many ml each jug holds to find the capacity.

The top jug has a scale of both pints (another measure) and ml.

The top jug has a capacity of ½ litre (500 ml)

The bottom jug has a capacity of 400 ml

The top jug has the greatest capacity.

In some questions, we are not given the measure but have to look at the size to estimate the capacity - what do you think the capacity of a bath would be, for example? We might find out in one of the following questions!

Let's get started!