Lesson video

Hi there.

My name is Mr. Tilstone.

I'm a teacher and it's really nice to meet you.

Today, we're going to do a lesson all about unit conversions.

Units of measure are everywhere.

Just look in your kitchen cupboard at home and you'll find all sorts of jars and labels with things like millilitres, and litres, and grammes, and kilogrammes on.

So today, we're going to explore the link between them.

If you are ready, I'm ready.

Let's begin.

The outcome of today's lesson is I can partition 1,000 in the context of measures.

So you've probably got lots of experience with the number 1,000.

Let's look at it in terms of measures.

Our key words today, my turn, metre, and millimetre.

Your turn.

And you might notice we've shortened metre down to m, that's an abbreviation, and millimetre, to mm.

My turn, kilometre, and metre.

Your turn.

And they can be abbreviated to km and m.

My turn, kilogramme, and gramme.

Your turn.

And they can be abbreviated to kg and g.

And my turn, litre, and millilitre.

Your turn.

And they can be abbreviated to l and ml.

It saves time.

So what do they mean? A millimetre or mm is a metric measure of distance used for small lengths, very small lengths.

The basic unit of length for distance in the metric system is metre or m.

A kilometre or km is a metric measure of distance.

A gramme or g is a measure of mass.

A millilitre or ml is a measure of capacity.

And today, we're going to explore all of those units of measure.

Our lesson is split into two cycles.

The first we'll be partitioning into 2, 4, 5, or 10 equal parts, and the second complements to 1 metre or litre or kilometre or kilogramme.

So two numbers that go together to make those.

So if you're ready, let's look at partitioning into 2, 4, 5, or 10 equal parts.

In this lesson, you're going to meet Andeep and Jun, have you met them before? They're here today to give us a helping hand with our maths.

Let's have a look at this.

This is a metre stick.

Have you got one of these in your classroom that looks a bit like this? Maybe it looks a little bit different.

What do you notice about this metre stick? John's remembered something.

He's remembered a useful conversion.

1 metre equals 1,000 millimetres.

Did you know that? I think you probably did, but it's useful as a reminder.

The metre stick is split into 10 equal parts, but it could be split into different numbers of equal parts.

So let's explore that.

What about that? How many equal parts can you see there? How about now? How many equal parts is that? It's still a metre stick, but it's split into different numbers of equal parts.

What about now? How many equal parts can you see there? All exactly the same.

How many are there? What could the sections be worth on each of these metre sticks? So we're going to see those divisions again.

This metre stick is divided into 10 equal parts.

What is each part worth? So remember, 1 metre equals 1,000 millimetres.

So that's 1,000 millimetres, what could each part be worth? There's 10 of them, 100 millimetres.

So they're all worth 100 millimetres.

Let's count along now in millimetres.

So we know they're worth 100.

Can you count in hundreds? I bet you've done that lots of times before.

Let's do it now.

100 millimetres, 200 millimetres, 300 millimetres.

It's easy, isn't it? 400 millimetres, 500 millimetres, 600 millimetres, 700 millimetres, 800 millimetres, 900 millimetres, and 1,000 millimetres, which we could say is 1 metre.

What about now? Let's have a look at this.

It's been divided into two equal parts.

It's still 1,000 millimetres.

What's each part worth? Half of 1,000, what's that? Do you know half of 10? That could be a useful starting point.

Half of 1,000 is 500.

So that's 500 millimetres, which means that's also 500 millimetres.

So let's count along in millimetres.

So this time we're counting along in steps of 500.

There's only two of them.

Ready? Let's go.

500 millimetres, 1,000 millimetres, and that's 1 metre.

What about now? This time it's split into four equal parts.

Now there might be something that you notice when you look at that one compared to the one we've just seen before.

Hmm, do you notice? So each of these are worth 250 millimetres.

So they're all worth that.

And I noticed that if you halved one of the parts in the middle model, it gave you one of the parts in the bottom model.

So that's how I worked that out.

Let's count along in millimetres now then.

So, we're counting along in steps of 250.

Are you ready? Let's go.

250 millimetres, 500 millimetres, 750 millimetres, and finally, 1,000 millimetres, which is 1 metre.

Well, let's do a little check.

This metre stick has been divided into, hmm, equal parts.

So that's an easy job for you.

You just gotta count the equal parts.

And each part is worth, hmm.

So remember how many millimetres are there in a metre? That's going to be helpful.

And then when you've done that, count along in those steps.

Pause the video and off you go.

Let's have a look.

Did you work it out? Well, the easy part, it's has been divided into five equal parts.

So, we are thinking what goes into 1,000, 5 times.

Well, I'm starting by thinking what goes into 10, 5 times, and that's 2.

So that's going to be a useful starting point.

So it's actually 200.

So each of those equal parts is worth 200 millimetres.

So shall we count along in steps of 200 millimetres? Well, let's go.

200 millimetres, 400 millimetres, 600 millimetres, 800 millimetres, 1,000 millimetres.

Well done if you got that.

This time we've got 1 kilometre.

1 kilometre is equivalent to 1,000 metres.

You knew that already, didn't you? I know you knew that.

What do you notice about the way the bar has been split? So have a look at that.

Do you notice anything? Does it look familiar? It might do.

It should do.

1 kilometre can be split into 10, 2, 4, or 5 equal parts in the same way as a metre can.

So just like we just looked at, this time with a kilometre.

So that means if it's split into 10 equal parts, one of those is worth 100 metres.

Does that look familiar? You've seen that number recently.

That means all of them are 100 metres.

So what about the next one that's been split into two equal parts.

What's each one going to be worth? 500 metres, just like before.

Right, this one split into four equal parts.

Well, you might remember and if you can't remember, you might be able to work it out.

What's each of those parts worth? I think 1,000 split into four equal parts is 250.

So they're all worth that.

What about the last 1? It's 1,000 split into five equal parts.

So what's each part worth? 200 metres.

So you could say 1,000 split into five equal parts is 200 metres.

Or you could say 1 kilometre split into five equal parts, each 1 is 200 metres.

Let's do a check.

Picture a set of scales that go up to 1 kilogramme, where the scale is split into 10 equal parts.

So just like this, how would the intervals be labelled? Pause the video and have a go.

Well, if it is 10 equal parts, we've actually done that twice already.

Can you remember? And can you work it out if not? It just looks a little bit different this time, but it's still 10 equal parts.

So each one would be worth 100.

So if each part's worth 100, we are counting in steps of 100.

So that goes, do it with me please, 100, 200, 300, 400, 500, 600, 700, 800, 900.

And they're all grammes.

And then after that, after 900 grammes is 1 kilogramme or 1,000 grammes.

So each of the values on this scale is a number of grammes.

Well, let's do another check.

You did well on that one.

Let's do another one.

What will the intervals be for a scale from 0 to 1 kilogramme marked in two equal parts, four equal parts, and five equal parts.

So what are those missing values? Pause the video and have a go.

Did you work it out? Again, this should look familiar to you.

This is very similar to what we've already done.

Okay, so this time we've got 1 kilogramme or 1,000 grammes.

That's our key conversion.

Split into two equal parts, making that 500 grammes.

What about the next one? So this time it's split into four equal parts.

So what would each one be worth? 1,000 split into four equal parts is 250.

So 250.

Then what's another 250? 500.

And another 250.

750.

So they're all in grammes, remember? And we could say that 1 kilogramme is 1,000 grammes.

And then what about the last one? This time it's split into how many equal parts? Five.

So what's 1,000 split into five equal parts? It's 200.

So we're counting in steps of 200 here, 200 grammes.

So 200 grammes, 400 grammes, 600 grammes, 800 grammes, and then 1 kilogramme or 1,000 grammes.

Well done if you got that.

It's time for some practise, I think you're ready for this.

The bar models represent metre sticks.

Give the length of the lines in millimetres.

So what's the length of A? What's the length of B? What's the length of C? What's the length of D? And E, F, G, and H? See if you can work those out.

Think how many equal parts that metre stick has been split into.

Number two, add the missing values.

So this time we've got a a measuring jug split into different equal parts.

So what's each part worth? And then what would the missing values be? And then number three, fill in the missing numbers here.

So we're counting in different steps.

They should look familiar to you, those numbers.

Welcome back.

How did you get on with that? Are you ready for some feedback? So number one, this first bar was split into 10 equal parts, meaning we're counting in steps of 100 millimetres.

That would go 100, 200, 300, 400 millimetres for A.

And then for B, I didn't count in 100 from the start, I just took 100 off 1,000, which was quicker, and that was 900 millimetres.

And then for C, so this has been split into two equal parts, so that's 500 millimetres for C.

And then 1,000 millimetres for D.

And you could even say 1 metre, that would be true as well.

For E, this has been split into four equal parts.

So each part is worth 250 millimetres and that is what E is.

And then for F, again, I took 250 millimetres off 1,000 to give me 750 millimetres.

For G, this one has been split into five equal parts, meaning each part's 200 millimetres, 200, 400, 600 millimetres for G.

And then for H, again, I took 200 millimetres off of 1,000 millimetres to give me 800 millimetres.

And the missing values, so A was split into 10 equal parts.

So they're the values, they're going in hundreds.

B was split into two equal parts.

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

And for C, that was split into four equal parts.

So they're the values for that.

And for D, it was split into five equal parts and they're the values for that.

We keep seeing these same numbers come up again and again, don't we? And the missing numbers for A, it goes 0 metres, 100 metres, 200 metres, 300 metres, 400 metres, 500 metres, 600 metres, 700 metres, 800 metres, 900 metres, 1,000 metres, which is also 1 kilometre.

And B, 0 millilitres, 250 millilitres, 500 millilitres, 750 millilitres, 1 litre or 1,000 millilitres.

C, 0 grammes, 200 grammes, 400 grammes, 600 grammes, 800 grammes, 1 kilogramme or 1,000 grammes.

And D, 0 millimetres, 500 millimetres, 1 metre or 1,000 millimetres.

You are doing really well.

I think you are ready for the next step, which is complements to 1 metre or litre or kilometre or kilogramme.

So let's have a look.

We've got a measuring jug here and what's the measurement on it? What can you see? So it's labelled, it's just got one marked interval and that's 1 litre.

Okay, and it's filled to 1 litre as well.

How many parts is it split into? Two.

Hmm.

So I wonder what the unmarked interval could be.

It might look familiar to you.

Now, if 500 millilitres of liquid is poured from that jug, how much will be left? So, we've got a bar here that shows 1,000 millilitres, which is the unit conversion for 1 litre split into two equal parts.

So each of those parts is worth 500 millilitres, and we're pouring one of them away, and that leaves us with this, 500 millilitres.

So converting that 1 litre into 1,000 millilitres was our first key step.

1,000 millilitres subtract 500 millilitres equals 500 millilitres.

Or you could say 1 litre subtract 500 millilitres equals 500 millilitres.

What about this one? Same amount of liquid it looks like.

And once again, just like before, it goes up to 1 litre or 1,000 millilitres, but it's split this time into 10 equal parts.

So if 300 millilitres of liquid is poured from the jug, how much will be left? Let's take away three 100s.

What's left? How many 100s are left? I can see seven 100s or 700.

So there we go.

That's the 300 millilitres poured away from that 1 litre and that gives us 700 millilitres.

1,000 millilitres subtract 300 millilitres equals 700 millilitres.

Or we could say 1 litre subtract 300 millilitres equals 700 millilitres.

Let's do a check.

If 250 millilitres of liquid is pulled from the jug, how much will be left? So remember my little tip, do that unit conversion first and then work it out.

Alright, pause the video and give it a go.

Did you manage to get an answer there? So starting with that unit conversion, we could think of it as 1,000 millilitres.

And 1,000 millilitres split into four equal parts, each of them is worth 250 millilitres.

And we're taking one of them away.

So that gives three equal parts of 250 millilitres and that equals 750 millilitres.

Very well done if you've got that, you're on track.

And the two equations we've got there, are 1,000 millilitres subtract 250 millilitres equals 750 millilitres, or we could say 1 litre subtract 250 millilitres equals 750 millilitres.

Let's have a look at this.

So we've got some weighing scales here.

How many grammes are being shown here? How many more grammes would make 1 kilogramme? Well, if you look at the scales, it's just measuring in grammes.

It's no mention of a kilogramme, but I can see a kilogramme on those scales.

Can you? One of those numbers means 1 kilogramme.

Do you know which one it is? It's the 1,000.

So, we've gotta get up to 1,000.

We've got 700 grammes so far, we've got seven 100s.

How many more would make 1,000? Three more.

So three 100s or 300.

There's 100, 200, 300.

And the equations that gives are 700 grammes plus 300 grammes equals 1,000 grammes or 700 grammes plus 300 grammes equals 1 kilogramme.

Let's have a little check.

Jun buys a 1 kilogramme bag of pasta and he uses 750 grammes of it to cook.

How much pasta is left in the bag? Remember my tip, you need to do a little unit conversion first, pause the video and have a go.

Did you manage to get an answer? So first of all, what's that useful unit conversion? Well, we're turning 1 kilogramme into grammes, and that's 1,000 grammes.

Now, he has used 750 grammes, so we could think of that 1,000 grammes being split into four equal parts of 250 and he's used three of them.

So 750 grammes have gone.

What's left? 250 grammes because 250 and 750 are complements to 1,000.

Together they make 1,000.

And the equation is 1,000 grammes subtract 750 grammes equals 250 grammes or 1 kilogramme subtract 750 grammes equals 250 grammes.

And it's time for some final practise.

Number one, circle the correct equation.

There's four different equations there, but only one is correct.

Number two, John's little brother is exactly 1 metre tall, his little sister is 100 millimetres shorter than that, how tall is she? Have you noticed there, there are mixed units, One's metre, one is millimetres.

Doing a conversion will help.

Number three, on a straight road, the mosque is 700 metres away from Oak Academy and then the library is 1 kilometres away.

How far is it from the mosque to the library? Again, a unit conversion will be helpful.

Number four, complete those calculations and there's a little bar model there that might help you.

Number five, the liquid from either jug B, C, or D is poured into jug A, which combination will give a total of more than, less than, or equal to 1 litre? Now remember, a unit conversion will be helpful.

Record the calculations to show this using less than, greater than, and equals to.

I think you're going to be amazing once again, good luck with it all and off you go.

Welcome back.

Would you like some feedback? Of course, you would.

Let's have a look.

So number one, the correct equation is this, 400 grammes plus 600 grammes equals 1 kilogramme because 1 kilogramme is 1,000 grammes.

Number two, John's little brother is exactly 1 metre tall and his little sister is 100 millimetres shorter than that, how tall is she? Well, 1 metre is 1,000 millimetres and if you subtract 100 millimetres from that, it gives you 900 millimetres.

And then, the mosque is 700 metres away from Oak Academy and the library is 1 kilometres away.

Or you could say the library is 1,000 metres away and then that becomes an easy equation to work with.

1,000 metres subtract 700 metres equals 300 metres.

And I actually counted on from 700 to 1,000.

I knew that was a 300-meter difference.

And number four, complete the calculations.

1 metre equals 500 millimetres plus 500 millimetres.

1 metre equals 700 millimetres plus 300 millimetres.

That makes 1,000.

1 metre equals 750 millimetres plus 250 millimetres.

D, 200 millimetres plus something equals 1 metre.

So what goes with 200 to make 1,000? It's 800 millimetres.

And E, 200 grammes, with 200 again, look, plus something grammes equals 1 kilogramme.

That's essentially the same thing we asked in D, 200 grammes plus 800 grammes equals 1 kilogramme because that's 1,000 grammes.

So F, 750 grammes plus 250 grammes equals a kilogramme, which is 1,000 grammes.

G, 750 metres plus 250 metres equals 1 kilometre.

And again, you might notice F and G are essentially the same question.

And then H, 100 millilitres plus 900 millilitres equals 1 litre.

Number five, so the jug A holds 700 mils of liquid.

You can see that split into 10 equal parts and there's seven of them.

So that means A plus B is greater than 1 litre because B holds 400 millilitres.

So, 700 plus 400 is greater than 1,000.

Now, A plus C is less than 1 litre.

As C is 250 millilitres, 700 plus 250 is less than 1,000.

And then finally, A plus D equals 1 litre because D is 300 millilitres.

So 700 plus 300 equals 1,000.

Well done if you've got that.

We've come to the end of the lesson.

I've thoroughly enjoyed it.

I hope you have too, and I hope you've learned lots.

The lesson has been all about partitioning 1,000 in the context of measures.

1,000 can be split into 10, 2, 4, or 5 equal parts.

1 kilometre, 1 metre, 1 litre, and 1 kilogramme can all be split in the same way as they are composed of 1,000 smaller units.

The bars show how 1 kilometre or 1,000 metres can be composed.

And you could have done the same thing with, for example, 1 kilogramme.

Congratulations on your achievements and your accomplishments today.

Why don't you give yourself a much-deserved pat on the back.

You have been amazing.

I really hope I get the chance to spend another math lesson with you in the near future.

But until then, take care.

Enjoy the rest of your day and goodbye.