Lesson video

Hello, and welcome to lesson seven, where we are just going to be recapping mass and capacity to make sure that we know how we look at intervals, how we estimate correctly, and we're going to be working with them together.

So we have a clear understanding of what the difference is between mass and capacity.

So let's start as always, we always start with the lesson agenda.

We're going to be starting of reading the scales.

Then we're going to move on to estimating mass and capacity.

So then we're ready to do an independent task and then get onto the answers.

Right, let's begin.

We will need as always a pencil, a rubber and an exercise book, ready to get on with your learning.

So what's the difference between mass and capacity? So what's the difference between mass and capacity okay? Remember that when we are dealing with mass, we are dealing with weights and how heavy something is.

And the units we've been working on has been grammes and kilogrammes.

We know that one kilogramme is equal to? That's it, 1000 grammes.

Therefore two kilogrammes is equal to 2000 grammes and five kilogrammes is equal to 5,000 grammes okay? And when we're dealing with capacity, we know that that is the amount of liquid that can be taken within a container all right? And we've spoke about the difference between the capacity and the volume.

Remember that volume is all of the space within that container.

And the capacity is when we're talking about the liquid that is within that container.

So really important that we know this because when we're talking about capacity, we use the units millilitres and litres, and we know that one litre is equal to how many millilitres? 1000 millilitres.

So two millilitres is equal to 2000 millilitres and five millilitres is equal to? That's it, 5,000 millilitres.

Well done guys.

It's good to remember the difference.

So let's begin with reading scales.

We're thinking back, what is it that we did before, okay? Five steps that we have to follow.

The first one, "The scale is measured in?" What are our scales? What are units? Kilogrammes, really good.

The indicator, which again, remember, is this arrow here okay? That is the indicator, is between, well, I say 200 and 300 kilogrammes, good? And the indicator, what's it closer to? Is it closer to 200 or is it closer to 300? And what is this value here? Well, if it's halfway between, I know that from 200 to 300 is 100 kilogrammes and half of 100 is 50, therefore this should be equal to 250.

I'd say it's close to 200 okay? Now I'm going to do my estimation.

I think that it would be something to, well, this will be about 210 to about 230 be here, so I'm going to go with 220 kilogrammes.

Therefore don't forget our final saying, "The mass of the parcel is around 220 kilogrammes." It's important that we say "around" because we're estimating it is not exact.

Well done guys.

Let's see what we can remember about the capacity.

Okay, reading scales in a container.

First step, "What is the scale?" Millilitres, well done.

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

We have 500 millilitres and 1000 millilitres.

Well done guys.

Now, "What is the value of each interval?" Now this is really interesting because we remember we need to work out if it's in between 500 and 1,000, then the value between there is 500 millilitres.

How many intervals are there? Let's count them ready.

And one, two, three, four, five, six, seven, eight, nine, 10.

Okay, there are 10 intervals okay? In 500 millilitres.

So 500 millilitres divided into 10 parts.

Hmm, let me think.

Is that a hundred? I'm going to try with 100, 600, 700, 800, 900, 1,000.

Okay, that's too high.

Could it be, if it's not 100, I might try something smaller.

I might go with half of one hundred so 50? Let's go with 50, 500, 550, 600, 650, 700, 750, 800, uh it's looking good, 850, 900, 950 and 1,000 really good guys! So therefore the value of each interval is 50 millilitres.

And sometimes it takes that trial and error.

Sometimes your timetables really help.

So really good guys.

So which interval is it closer to? So let's have a look then if it's 50, then 500, 550, 600, 650, 650 right there.

And my estimation, well, the capacity is right underneath it.

So it was not exactly 650.

So the sentence I'm going to say is there is about 645 millilitres in the container.

Don't forget the units okay? And we say "It is about" because it is a? That's it, it's an estimation.

Really good remembering guys, really proud of you.

It's time for you guys to have a go by yourselves.

Right, so reading scales, we have the mass of a parcel and the capacity of a jug.

Remember that it's important that we use the correct vocabulary, mass of a parcel, that's the weight, the capacity of the jug.

I would like you to pause this video and I'd like you to give it a go.

Make sure that you're following all the steps, looking at the intervals, it is so important for you to figure out the value of the intervals for you to get a good estimate.

Pause the video now please.

Good luck.

Okay, you are back with me.

Are you ready? Let's find out, the correct answer was The jug was about 225 millilitres and the parcel was about 140 kilogrammes.

Let's find out how we got there.

Okay, so let's look into this parcel first.

So first thing we need to do is, is the scale.

The scale is? Kilogrammes okay? Really good.

"The indicator is in between?" And in this case, indicators is red line right there.

And it is in between 100 and 200 kilogrammes.

Really good guys.

Now "The indicator is closer to," now, which one is it closer to? Before we do this, we need to work out the values of intervals, right? And we know what to do with this.

We're confident, we got this guys.

So let's count how many intervals there are between 100 and 200.

One, two, three, four.

Okay, there's four intervals in between 100.

Well, I know that this is half way and half of 100 is 50 and this is half way as well, so half of 50 is 25.

Therefore I think each interval is equal to 25.

So I know that the indicator is close to 100 kilogrammes.

Now because I know each interval is equal to 25, I can count from hundred, 100, 25, 50, 75, 200.

And I'd say it's closer to 150 right now, isn't it? So my estimation is going to be about 140 kilogrammes.

That's going to be my estimation.

Therefore, my final sentence is "The mass of the parcel is around 140 kilogrammes." Really important we find out those intervals guys, always going to be something that we need to know before we do our estimates.

Okay, let's see how we got to the capacity of this container.

First step has always, "What is the scale?" The scale is millilitres, really good.

"What two intervals is in between?" Well in this case, it is in between 200 and more, we don't know what's up there.

That's as far as it goes, so I'm going to write 200 millilitres and more.

"What is the value of each interval?" Well, in order to find that out, I'm actually going to use from zero to 100 millilitres okay? And I'm going to count my intervals first.

So one, two, three, four.

It's very similar to the last one.

If I know that the value from here to there, from zero to 100 is 100 and it's split into four parts, that means I need to figure out what each interval is.

So halfway here, half of a hundred is 50 and half 50 is 25.

And you see we, we become quicker at this because of all the practise that we've been doing, practise makes permanent guys.

So each interval is equal to 25 millilitres.

Now, "Which interval is the volume closer to?" So I'm going to look at 200 and because each interval is equal to 25, I'm going to count up in 25, 200, 225, so there it is.

So my estimation is, there is about 225 in the container.

That's what I'm going to go with guys.

Well done for remembering, let's move on to the next part of our lesson.

Okay, estimating mass and capacity.

So first we're going to start with mass and look, we're back to seeing these signs, again, "More than" or "Less than" really important that we remember to use that because remember that we know that "More than" is this sign and "Less than" is this sign.

Really good remembering guys.

So here we go.

So before we start, let's see what we have in front of us.

We have a mass of 500 grammes, we have a tin of food and we have our inequality.

Now what inequality is this? This is "Less than" right? No, it's not, absolutely not.

Well done, thank you for correcting me.

This is "More than" or "Greater than".

So what we can see from this picture is that the mass is greater than the tin of food, okay? It's "Greater than" so therefore the tin of food is less than 500 grammes.

So let's read it.

I know this mass weighs 500 grammes.

The tin of food feels now that's a key word here okay? Can we all say feels? Feels a little bit lighter? Cause that's the best way really, to estimate when you're dealing with, with mass, isn't it? When you get this feeling, when you compare them both.

So I estimate the mass of the tin is going to be, my estimate is going to be about 400 grammes.

And the important thing is, is that it is less than 500 grammes and it's only a little bit less, okay? So I'm not going to go for 10 grammes or five grammes because it says a little bit less, I've decided to go with 400 grammes.

So the mass of the tin of food is 450 grammes.

As Suzie has weighed that for us.

So we were really close.

So we we're right, it is lighter than 500 grammes.

And again, these are the key words that we're using "Feels" and "Lighter" okay? So when we're dealing with mass, we're all about how it feels.

Okay, So now we're going to start estimating capacity.

So having a look at the image, we always acknowledge the capacity of what we're comparing to.

And in this case, it's a 500 millilitre bottle of water, okay? And here is our sign "Less than"? Good listening, "Greater than" so 500 millilitre's greater than this can of pop, okay? Which means that this can of pop is less than, okay, if you look in it this way can of pop is less than 500 millilitres.

So let's start with our conversation here then.

I know that the capacity of the water bottle is 500 millilitres.

The Cola can looks, okay? This is the key word, whereas in mass, we said "Feels", cause it's all about it feels when we're trying to estimate capacity, we're going to say, "It looks".

It looks about, I'd say half the size of the water bottle.

So I estimate that the Cola can has capacity of, well, if I know that half of 500 is 250, then I'm going to say 250 millilitres.

Now Suzie comes along and she's been great, she's actually measured it for us.

So she says "I've measured the capacity of the Cola can.

"You we're right! "It is smaller than the water bottle "with a capacity of 350 millilitres." Okay, so your turn.

All right, so estimating mass and capacity.

I would like you to find an appropriate estimate for the mass of the book and an appropriate estimate for the capacity of the fish tank.

Now, look at the images, okay? And remember our inequalities cause that's what's going to help you.

"Greater than" or "Less than".

Always pause the video and I'd like you to choose the appropriate answer.

Off you go! All right, welcome back guys.

So let's see what we got.

The answer should have been, ready? Boom! This is your answer.

The book is about 350 grammes and the tank is 750 millilitres.

So let's see why, okay? Having to look at this picture first, let's read it together.

500 grammes is greater than the book, okay? That means that the book can't go any higher than 500 grammes, which is why we have given it a mass of 350 grammes, okay? Now, yes.

Now it means that we have these two as our options.

And we know that this is not an option because we measure mass in grammes or kilogrammes, not in millilitres, okay? So we're now stuck with these two, which one's going to be? Let's have a look at the next one.

500 millilitres is less than the tank.

That means that there is more capacity in this tank, okay? That means there's more than 500 millilitres in this tank.

So if we have a look at both our options that we had, 350 grammes, the tank is 350 millilitres and 750 millilitres.

So which one is more than 500 millilitres? This one right here.

And that is why that is the correct answer.

Really good guys, I'm really impressed.

I think you guys are ready for the independent task.

I can't wait, here we go.

Okay guys, here we go.

Independent task time.

I really want you guys to work out these values for me.

You're going to pause the video now and you're going to go to your worksheet and you're going to complete this task.

And then come back to me when you are finished.

Good luck! Remember everything that we've learned and I'm sure you guys are going to be amazing.

Okay, so answer number one.

So here we're measuring capacity and that, that's right.

We are not measuring capacity where we are, we are measuring mass.

Well done guys, staying alert here.

So the scale is measured in? Grammes, really good.

Okay, so "The indicator is in between," well we have 500 and 600 grammes.

Well done.

The indicator's closest to, well before we do that, let's figure out what the value of each interval is.

If from 500 to 600 is 100 grammes and we only have, and we have, this is 100 grammes and this is half way, well, half of 100 is 50 so this must be 550 okay? So therefore our indicator is closer to 550 grammes.

So our estimation.

Well it not exactly 550 grammes, so that can't be the right answer.

So I'm going to go for about 540 grammes.

Therefore our final sentence is, "The mass of the parcel is around 540 grammes." Good work guys.

Let's move on to the next one.

Okay, so here we're going to be measuring mass and ah, well done.

It is capacity, okay? Remember when we're dealing with volume is with capacity.

It's the first step, "What is the scale?" The scale here is millilitres.

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

Now I know this is a bit confusing and I put arrow in your worksheet, but this is actually where the capacity is showing, okay? Right there.

And it is in between, Oh, well I was going to put zero and 25, but then I realised that this is half of 50, which I know is 25.

So then it is in between 25 and 50 millilitres.

So what are the value of each intervals? Well, let's count them, one, two, three, four, five, six, seven, eight, nine, 10.

That means that 10 parts divided equally into 50.

Oh I know my five times tables are going to help me here because I know that five times 10 equals 50.

Therefore each interval is equal to five millilitres.

Let's just check though, because I want to make sure, mathematicians always check.

Here we go, Five, 10, 15, 20, 25, 30, 35, 40, 45 50.

Good, feel better now that we've checked it.

So which interval was the volume closer to? Well let's have a look.

If this is 25 and this is 30, I'd say it's closer to 30 millilitres.

And my estimate is going to be, "There is about 32 millilitres in the container" because it's not quite on 30 millilitres, but it is quite close, but it's a bit more than that, okay? So it's not less, it's more than 30 millilitres.

Well done guys.

Let's move on to the next question.

Okay, so let's go into the next question when we are going to be estimating the mass of this oil, okay? So having a look first at the picture, we're going to acknowledge that this is 500 grammes this is the mass that we're comparing it to.

And this sign here is "Less than" oil.

So it's saying that this 500 grammes is less than this oil.

That means that this oil weighs more than 500 grammes.

So I know the mass weighs, as we said, 500 grammes, the oil feels twice as heavy as the weight.

So it's twice as heavy, that's really important.

If it's twice as heavy, that means that it's times two.

So 500 grammes, times two is equal to 1000 grammes.

And what is that in kilogrammes? That's right, one kilogramme.

Therefore, we can say that this olive oil is one kilogramme.

Really good work guys.

Let's go to the next one.

Okay, capacity.

So I know the capacity of this water bottle as always, we start with the image and we acknowledge what we're comparing to is 500 millilitres.

Okay, the pan looks slightly smaller than the bottle.

So I estimate the capacity of the pan.

Well, have a look at the inequality as well cause that's really important.

It says here the 500 millilitres is greater than the capacity of this pan.

So because it's slightly smaller, we're going to go for 450 millilitres, only because it's slightly.

If it said that it was half the size, then it would be 250 millilitres.

If I said that it was a lot smaller, okay? Then I would maybe go for 200 millilitres, but because it said slightly smaller, I've decided to go with 450 millilitres.

Well done guys! Great work, I'm really proud of you guys.

I hope that with these steps and with these lessons that we've just had, they're going to help you with any questions that you come across with mass and capacity.

Well done and good luck with the rest of your learning for today.