Lesson video

Hello, welcome to our next lesson where we will be looking at measuring volume and capacity.

So before we start, we're going to look at our lesson agenda.

So first we're going to be identifying the value of intervals on a scale, which we've done before when we're looking at mass.

We're going to be practising rounding volumes in millilitres, and then we're going to move on to our independent task and then our answers.

So, you will need a pencil, a rubber and an exercise book to do these activities.

So I thought we start with this question.

Does every piece of equipment used to measure volume, use the same scale with intervals of the same value? So let's have a look at these different equipments.

We have a bucket, we have a measuring beak.

Okay, you have a spoon.

Okay, we have cylinders.

We have measuring flasks.

Do they all use the same scale? Now as you can see from here they don't do that.

And the reason why is because different liquids or different amounts will require different scales.

So if you're only going to measure a small amount of a liquid, then you don't need a very big bucket.

However, if you need to measure a very high amount of a liquid, then you will need a bigger bucket which would mean bigger scales.

Okay, so the terms volume and capacity are used interchangeably.

That means that you can use either or.

Because the differences are really subtle.

They're very small.

Now volume is the amount of 3D space, an object occupies or takes up, okay? So this is the space inside here, the volume.

Now capacity, we can refer to as the total amount of fluid, I want to add it just in here.

Okay? Just to the top there you got to be really careful.

That can be contained in a container and the word we use when we are measuring liquids.

Right? So when I'm talking about volume, I'm more on about the space inside of this glass.

And then when I'm talking about capacity, I'm talking about the fluids or the liquids inside of the glass.

Bottoms up.

So now that we have distinguished between volume and capacity, we now need to think about the units that we will be using.

And they are going to be litres and millilitres, okay? Very similar how we did a mass where we looked at kilogrammes and grammes.

Now, it's very important for you to know this that one litre is equal to 1,000 millilitres.

Therefore two litres is going to equal to 2,000 millilitres.

And it's the other way round as well, where 1,000 millilitres is equal to one litre and 2,000 millilitres is equal to two litres.

And just so you have a rough idea of what it looks like, in this beaker, you can see that 1,000 millilitres which is one litre compared to what one millilitre looks like.

So the difference is very big.

Okay so let's start off with identifying the value of intervals on a scale.

Now we've done this before, but in this case, the scale is just vertical, okay? It's not in a circle like we would in a scale.

Okay well it's not horizontal like in scales that we've seen before.

This one is vertical.

So we need to ask ourselves those three questions.

How many intervals are there? Okay? Number two, what is the value between these intervals, in this case zero millilitres and a thousand millilitres? And number three, what is the value of each interval? So first question, how many intervals are there? Well let's count.

There is one, two, three, four, five, six, seven, eight, nine, and 10.

Good, so we know that there are 10 intervals in this measuring cylinder.

So what is the value between zero millilitres and 1,000 millilitres? Well that's 1,000 millilitres.

And that's going to help us with number three, which is what is the value of each interval? So if I know there are 10 intervals that make up 1,000 millilitres, I'm going to use my Ten Times Table to help me, I think.

10, 20, 30, 40, 50, 60, 70, 80, 90, a hundred.

If I know that, then I can say a hundred, 200, 300, 400, 500, 600, 700, 800, 900, 1,000.

That means that each interval is going to equal to? 100 millilitres.

Right, awesome.

Let's go on to the next one.

So this is going to be the question that we're going to work together in.

So the first thing we do is how many intervals are there? Now we are going to be looking at, this specific red box here.

We're not going to look at past 700 millilitres.

We don't need to, we can just focus on that little space there.

Now looking at that box, how many intervals are there? Let's count together.

One, two.

Perfect, really good.

What is the value between zero and 100 millilitres? 100 millilitres.

Now what is the value of each interval? Now there's only two intervals in between, so I need to work out what half of 100 is.

And that is 50.

Therefore, each interval is equal to 50 millilitres.

Alright now it's your turn.

So what is the value of the intervals? That is what I want you to find out first.

So remember our three steps.

What are they? They are, how many intervals are there? What is the value between those intervals? And then what is the value of each interval? Pause the video and try this for yourself.

Okay, amazing.

Let's have a look then.

So what is the first question? How many intervals are there? So let's have a look.

We're going to go from one, two, three, four.

There are four intervals in between 1,000 millilitres which we know is one litre.

And so 1,000 is divided into four parts.

Well if I know half of 1,000 is 500, which is that.

And half of 500 is equal to, what exactly is it equal to? 250 millilitres.

Well done.

That should be your answer, 250 millilitres.

Okay, now that we are confident with knowing our intervals, now we need to start practising rounding volume in millilitres.

So again, five steps.

I always try to keep things with into steps, so we know how this works.

Number one is what is the scale? What's number one? What is the scale? Two, what two intervals is it in between? Three, what is the value of each interval? Four which interval is the volume closer to? And five, make your estimation.

So let's answer the first question.

And the first one is what is the scale? Where we know the scale is millilitres, okay? What two intervals is it in between? We're going to go with 500 millilitres and 1,000.

Now compared to a scale, so a weighing scale, normally you would have an indicator.

In this case, the water, okay? Or the capacity in there is the indicator.

So it's in between 500 and 1,000 millilitres.

What is the value of each interval? Now we're using our school from before.

So first step we need to figure out, how many intervals there are in between here? One, two, three, four, five.

So there are five intervals in between the 500 and 1,000.

What is the value between that? That's 500.

If there's five intervals in between 500, the best fit there must be a hundred, right? Cause it would go 600, 700, 800, 900, 1,000.

So the value of each interval is 100.

Good.

Which interval is the volume closer to? Well, it seems a lot closer to 700, right? Let's have a look.

600, 700 right there.

And now in that case, I'm going to make an estimation.

It's just under.

So I've gone for, there is about 690 millilitres in the container.

And that is my final sentence.

We're going to say that together three two one, "There is about 690 millilitres in the container." Right? I'm ready you guys.

You're going to help me answer the next one.

Let's go.

Okay, now it's time to do one together? So what do we do first? That's it.

What is the scale? And the scale is? millilitres.

Well done.

Number two, what two intervals is the capacity in between? Okay? And we can see from here that it is in between 500 and 1,000, Okay? What is the value of each interval? Now in order for us to figure that out, we know all this already.

Okay so we need to count how many intervals there are in between 500 and 1,000.

Let's count, one, two, three, four, five, six, seven, eight, nine, 10.

So there's 10 intervals.

And what is the value in between these intervals? Well from 500 to 1,000 is 500.

So that's 500 divided into 10 parts.

Could it be a hundred? Let's try that.

Let's go from 500, 600, 700, 800, 900, 1,000.

That's too much.

Could it be 10 maybe? Should we try 10? 510, 520, 530,540 500, 550 560, 570, 580, 590, oh no.

Well if it wasn't 10, if it wasn't a 100, then maybe 50.

Should we try 50? Here we go.

500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1,000.

There you go guys, the value of each interval is 50 millilitres.

Now which interval is the volume closer to? Well, let's have a look.

It's right there.

It's pretty much on that interval, Isn't it? So should we count up in fifties? 550, 600, 650.

Yeah, that's the one we're going to go with.

So our estimation is not actually on 650, but it's so close to it.

So remember what we say? There is about 645 millilitres in the container.

Something like that.

That is an estimate that we're going to go with, okay? Really good guys.

Now it is time for you.

So practising rounding volume in millilitres.

What is the volume of this container? I would like you to pause the video, and follow the steps that we go through.

The five steps.

Off you go.

Okay, back to me.

So, the right answer would have been, 63 Millilitres is the one we're going to go for.

Let's check.

Let's check.

What were the five steps? So what is the scale? The scale is, millilitres.

And then we need to figure out, well where is the capacity in between? Well it's in between 50 and 100, okay? Now we need to figure out what is the value of the intervals? So let's have a think.

Well we have one, two, three, four, five.

So that's 50 divided into five parts.

That means that each part must equal to 10.

So let's find out let's check, cause we have to check first.

So if it's equal to 10 it will be 50, 60, 70, 80, 90, a hundred.

Good.

The fourth step is, well what interval is the capacity close to? So let's find out.

Well it's closer to 60 or 70 yeah.

It's a lot closer to 60, okay? Now in that case, all of these are 60 60, 63, 65, 68.

We know it's not 60 millilitres because it would be this interval here.

We know that it's not 65 millilitres cause then it would be exactly in the middle which would be a little bit higher.

We know that it's not 68 millilitres cause then it would be a lot closer to 70 millilitres.

Therefore the answer is 63 millilitres.

Well done guys.

All right, time for the independent task.

Now you need to help me to read the correct volumes of water for my plants.

It is important that they don't have too much or too little water if they're going to remain healthy.

Especially in this really unpredictable weather.

Where it's really hot and humid, okay? So you're going to be pausing this and you're going to go to the worksheet and you're going to use all of those steps that we've learned in today's lesson to get you through these questions.

I wish you all the best.

Remember the five steps, okay? And counting your intervals.

It's so important to figure out what the intervals are.

Good luck.

Okay.

Time for the answers.

So let's start off with the first one.

First question, what is the scale? Well, it's not millilitres.

Be careful.

It is in litres this time, okay? So what two intervals is it in between? Well, let's have a look.

It is in between 30 litres and 40 litres.

Number three, what is the value of each interval? Well if we know that from 30 to 40 is 10 litres, and there are two intervals in between.

That means that it's 10 litres divided into two parts.

So what's half of 10? Five litres.

Well done.

Which interval is the volume closer to? Well let's have a look.

It's closer to 35 litres.

Now be mindful that it's not exactly on 35.

It's just underneath.

Therefore an estimate has to be just underneath 35 litres.

And I'd say there is about 34 litres in the container.

Okay, so let's go into the next one.

First thing we need to do is? What is the scale? Good.

And the scale here is? Millilitres, right.

What two intervals is it in between? Well let's have a look.

It is in between, it's right here.

So it's in between zero and 50 millilitres.

Excellent.

What is the value of each interval? Right.

So how many intervals are there here? One, two, three, four, five, six, seven, eight, nine, 10.

And from zero to 50 is 50.

So the 50 millilitres is going to be divided into 10 parts.

Okay.

Well I know that 10 times five equals 50.

So therefore each one should equal to five millilitres.

That's what's going to help me.

So, okay.

So which interval is it closer to? Well let's have a look.

If half of 50 is 25, then this is 25.

Let's count up in fives.

25, 30, 35.

I'd say it's closer to 30 millilitres.

Good and now my estimation, it isn't exactly on 30 millilitres but it's just above it.

So I'm going to go with, there is about 31 millilitres in the container.

Right.

Good.

What is the scale millilitres, right? No, it is litres.

Well done.

What two intervals is it in between? Well let's have a look.

It's in between 10 litres and 20 litres.

Well done.

What is the value of each interval? Well, if from 10 to 20 is 10 litres and there are one, two, three, four, five intervals.

Could it be 10? Well it can't be 10 because that's 10.

Is it one? one, two, no.

11, 12, 13, 14, 15 two, 12, 14, 16, 18, 20.

Good.

So each value of each interval is two litres.

Well done.

Which intervals is it closer to? Well it's closer to this one.

If each interval is two litres, then there'll be 10, 12.

So it's closer to 12 litres.

Okay? Now we need to make an estimation.

Now it's just above 12 litres.

So I would say that there is about 13 litres in this container.

Okay, number one.

What do we do first? What is the scale? And we're dealing with? Millilitres.

Well done.

What two intervals is it in between? Well, let's have a look.

It's right at the top here.

So actually we have it's from 200 millilitres and above, okay? I'm going to say and more.

What is the value of each interval? Now this is tricky because we don't know what's above here.

So I'm going to go from zero to a hundred.

Let me just see what it is from zero to a hundred.

How many are there? One, two, three, four intervals in between zero to a hundred.

Okay, well, if half of a hundred is 50, then this would be 50 and half or 50 is 25.

So therefore the interval should be equal to 25, okay? Let's just double check.

25, 50 75, a hundred, 125, 150, 175, 200.

And then it's going to help us with the next one.

Which interval is the volume close to? So this would be 225 millilitres.

Now we have to make an estimation.

Now it's just underneath it, okay? So 225 wouldn't be a good estimation.

It's just underneath it.

So we're going to go with, there is about 223, 224 in the container, using all of our skills.

You worked really hard today guys.

Well done.