Lesson video

Hi there.

How are you today? I hope you're having a really good day.

My name is Miss Coe.

I'm really excited to be learning with you today as we explore the 2, 5 and 10 times table, and the relationships between them.

If you're ready, let's get started.

In this session today, we are focusing on the 10 times table, and by the end of this lesson you'll be able to say that you can explain the relationship between adjacent multiples of 10.

Now, you may have come across this word "adjacent" before, and you may have some idea of what it means, but if not, don't worry.

By the end of this lesson you will have a good understanding of thinking about these multiples.

We have two key words in our learning today.

I'm going to say them and I'd like you to say them back to me.

Are you ready? My turn.

Previous.

Your turn.

My turn.

Next.

Your turn.

Great job.

Keep a close eye out for these words in this lesson today, and see if you can use them when you're talking to your partner about your learning.

In this lesson today we're going to be explaining the relationship between adjacent multiples of 10, and our lesson has two cycles.

In the first cycle we're going to be looking at adjacent multiples of 10, and then in the second cycle we're going to be finding adjacent multiples of 10.

So if you're ready, let's get started with the first cycle of our learning.

In this lesson today, you're going to meet Aisha, and Laura, you may have met them before.

They're going to be helping us with our learning today.

So let's start here.

Look at the objects below.

Can you describe them? What do you notice about them? So we have a base 10 block and you might be familiar with using base 10 in your learning.

We have a 10 pence coin and we have a packet of sweets.

What do you notice? All of these objects represent a value of 10.

So the base 10 block is made up of 10 individual cubes.

It has a value of 10.

The 10 pence coin represents 10 lots of one pence, and if you look really carefully at that packet of sweets there are 10 individual sweets in that packet.

Each of these represent 10.

So if I were to have three base 10 blocks, I could say that was three groups of 10.

Let's think about that a little bit more.

Aisha is going to use these base 10 blocks to explore multiples of 10.

Maybe you have some base 10 blocks yourself, and you would like to use them to represent the multiples of 10 like Aisha has.

We can think about the relationship between multiples of 10 like this.

If we look at 30, we can say that 30 has one more group of 10 than 20.

We can show that using the base 10 blocks.

20 has two groups of 10 or two sticks.

30 has three of those sticks, so it has one more group of 10 than 20.

What other relationships can we say? Well, we can also say that 20 has one fewer group of 10 than 30.

If we look at 30, it has three groups of 10.

20 has two groups of 10.

20 has one fewer group of 10 than 30.

If we look at 40, we can say that that has one more group of 10 than 30.

We can also say the opposite of that.

We can say that 30 has one fewer group of 10 than 40.

Let's keep that in mind while we think about packets of sweets.

Aisha records the number of sweets which are in packets of 10.

She records the multiples of 10 in order so we can see that she started with no packets of sweets.

If there are no packets of sweets, then there are no sweets.

0 multiplied by 10 is equal to 0.

There's nothing there.

If we have one packet of sweets, that is one group of 10 which is equal to 10.

2 packets of sweets is 2 groups of 10, which is 20.

3 groups of sweets is 30, and 4 groups of sweets is 40.

She has started to write the multiples of 10 in order, 0, 10, 20, 30, 40.

I wonder if you could say what comes next? Take a close look.

What patterns do you notice in the table that Aisha has created? Well, you may have noticed some of the things that Aisha has noticed.

Aisha's table shows adjacent numbers.

These are just numbers that are next to each other, so she can say that 10 has one more group of 10 than 0.

30 has one fewer group of 10 than 40, and we looked at that earlier with the base 10 blocks.

Adjacent multiples, multiples that are next to one another have a difference of 10.

So if we move down the column of multiples of 10, we are adding 10.

It increases by 10 each time.

Let's take a look at that.

0 plus 10 is equal to 10.

The next multiple of 10 is 10 and that's 10 more than 0.

If we go down again, 10 plus 10 is equal to 20.

The next multiple is 20, which is 10 more than 10.

And we can say that for any of them going down that column.

If we move up the column, however, the product decreases by 10.

So if we start at 40.

40 subtract 10 is 30.

So we can say that the previous multiple of 10 is 10 less than 40, which is 30.

If we have 30, 30 subtract 10 is 20.

So we can say the previous multiple of 10 is 10 less than 30, which is 20.

Aisha is trying to find the next multiple of 10 in her table so we can see that four packets have 40 sweets, five packets have 50 sweets, six packets.

Hmm.

How can we work it out? "Well to find the next multiple I need to add 10," says Aisha.

Remember if we're going down that column, it increases by 10 each time.

What is 10 more than 50? 10 more than 50 is 60.

50 plus 10 is equal to 60.

And we can say that 60 has one more group of 10 than 50.

Time to check your understanding.

Look closely at the table.

Can you find the next multiple of 10? Hmm has one more group of 10 than 60.

Pause the video here and have a think.

Welcome back.

Remember, if we're finding the next multiple of 10, we need to add 10 to the multiple of 10 that we know.

60 plus 10 is equal to 70.

So we can say that 70 has one more group of 10 than 60.

Remember if we're thinking about the table when we move down that column, the product increases by 10 each time.

Well done if you said that 70 would be the next multiple of 10.

This time Aisha is trying to find the previous multiple of 10.

She remembers that to find the previous multiple of 10 she needs to subtract 10.

We know that eight groups of 10 is 80, so to find the previous multiple we need to subtract 10 from 80.

80 subtract 10 is equal to 70, so we can say that 70 has one fewer group of 10 than 80.

When we move up the column, the product decreases by 10.

Time to check your understanding again.

The previous multiple to 90 is hmm.

Think about what you need to do if you're going up the column.

Pause the video here and have a go.

Welcome back.

Well remember if we're going up the column, we need to subtract 10.

90 subtract 10 is 80, so the previous multiple to 90 is 80.

80 has one fewer group of 10 than 90.

Well done if you said that.

Aisha continues to look at multiples of 10, but this time she's using a number line.

We can see the number line here has the multiples of 10 from 0 to 120.

Let's count them together.

Are you ready? 0, 10, 20, 30, 40, 50, 60, 70, 80, 90.

100, 110, 120.

Well done.

We can show adjacent multiples of 10 here too.

If we start at 0 and add 10, we get to the next multiple of 10, which is 10.

What happens if we add 10 more? That's right.

We get to the next multiple of 10, which is 20.

We can say that 10 more than 10 is 20.

If we add another 10, we get to the next multiple of 10, which is 30.

We can say that 10 more than 20 is 30, and we could keep going along this number line, adding 10 each time and getting to the next multiple of 10.

Every time in fact, you do a jump on the number line to the right, it is 10 more.

We add a group of 10 to get to the next multiple of 10.

If we add 10 to any multiple of 10, it gives us the next multiple of 10.

So we could start anywhere on that line, and if we added 10, we'd get to the next multiple of 10.

So we can say the next multiple of 10 to 20 is 30.

This time Aisha thinks about the previous multiple of 10.

If we start at 110 and subtract 10, we get to 100, which is the previous multiple of 10.

If we subtract another 10, we get to 90, which is the previous multiple of 10.

We can say that 10 less than 100 is 90.

Both of them are multiples of 10.

If we subtract another 10, we get to 80.

We can say that 10 less than 90 is 80.

Subtracting 10 from a multiple of 10 gives the previous multiple of 10.

Every time you do a jump on the number line to the left, it is 10 less.

We subtract a group of 10 to get to the previous multiple of 10.

So we can say that the previous multiple from 90 is 80.

Time to check your understanding.

Can you tell me the previous and next multiples of 10 for 60? Think about whether you're adding or subtracting 10.

Pause the video here and have a go.

Welcome back.

Well if we want the next multiple of 10, we need to add 10.

10 more than 60 is 70.

If we want the previous multiple of 10, we need to subtract 10.

10 less than 60 is 50.

So the previous and next multiples of 10 for 60 are 50 and 70.

Well done if you identified both of those.

Time for your first practise task.

Work with a partner if you have one.

Take it in turns to pick a multiple of 10 from the list below, and place it in the correct place on the number line.

Explain your choice every time.

Can you use the words "previous" and "next"? Remember, they're are keywords, when you're explaining.

For Question 2, I'd like you to find the missing multiples of 10 and complete the sequences.

So you've got 0, 10, hmm.

What is the next multiple of 10? Pause the video here, have a go at those two tasks, and come back when you're ready for some feedback.

Welcome back.

How did you get on? For Question 1 here is the completed number line.

Let's skip count in tens to check that we've got all the numbers in the right place.

0, 10, 20, 30, 40, 50, 60, 70, 80, 90.

100, 110, 120.

That's the completed number line, but what I'm really interested in is thinking about how you explained where you placed the numbers.

For example, Aisha has done a great job.

She says, "I put 10 here because it is adjacent to 0.

It's the next multiple." She could say that 10 more than 0 is 10.

So 10 is the next multiple.

I really hope that you used the words "previous," and "next" when you were describing the positioning of your multiples of 10.

For Question 2 you had some sequences to complete.

Let's take a closer look at A.

0, 10, hmm.

Well the next multiple was 10 more than 10, which is 20.

We then had 10, 20, hmm.

The next multiple is 30 because it is 10 more than 20.

We're adding 10 in both of those examples.

For the next one we had to find the multiple that was in between 40 and 60.

There are two ways you could have thought about this.

You could have said the next multiple to 40 is 50, because it is 10 more.

You could have also thought about the previous multiple.

The previous multiple for 60 is 50 because it is 10 less.

60 subtract 10 is equal to 50.

The same can be said for the last example in A.

80, hmm, 100.

10 more than 80 is 90.

Or 10 less than 100 is also 90.

Well done if you reasoned using previous and next multiples.

Take a close look at B and C to make sure that you have those sequences correct.

You've worked really hard in cycle one.

Let's take a look at the second cycle where we're finding the adjacent multiples of 10.

Let's start here.

Laura has a collection of sweets.

Remember our sweets are in packets of 10.

She can say that she has 3 groups of 10, which is 30 sweets altogether.

She can write the multiplication equation, 3 multiplied by 10.

Three groups of 10 is equal to 30.

Andeep comes along, and he gives Laura another packet of sweets.

Here we go.

We can see that extra packets of 10 sweets.

We can say that 4 groups of 10 is one more group of 10.

So we've added a group of 10 to what Laura already had.

Like so.

We can write this as an equation.

So we can say that 4 groups of 10 is equal to, or is the same as, 3 groups of 10 plus 10.

Let's see how that image shows that.

We started off with 3 groups of 10.

We added a group of 10, so that's the 3 multiplied by 10 plus 10 bit.

We now have 4 groups of 10 or 4 multiplied by 10.

There are 40 sweets altogether now because there is another group of 10 added.

It was the next multiple.

Time to check your understanding.

Look carefully at the image.

Andeep gives Laura another packet of sweets.

So she had four packets of sweets, and he gave her another packet of sweets.

She now has five packets of sweets.

How many sweets are there all together? Can you complete the equations? Pause the video here and have a think.

Welcome back.

Now some of you may have found this a bit tricky, so let's go through it carefully together.

We know that altogether there are 5 groups of 10.

5 groups of 10 is equal to 50.

So we know there are 50 sweets altogether, but that first equation is a little bit more tricky.

Remember we started off with 4 groups of 10, 4 multiplied by 10 and we added an extra 10, or one group of 10.

So we can write 4 multiplied by 10 plus 10 is equal to, is the same as, 5 groups of 10.

And we know that 5 multiplied by 10 is equal to 50.

Well done if you reasoned and thought carefully about that first equation in particular.

This time Laura is giving away a packet of sweets to one of her friends.

Let's see what she does.

She had 3 groups of 10 sweets, and we know that 3 groups of 10 is equal to 30.

So she's given a packet of sweets away, and we can say that she now has 2 groups of 10, which is one fewer group of 10 than she had before.

So we can write an equation for this as well.

She now has 2 groups of 10, 2 multiplied by 10, which is equal to 3 groups of 10, subtract or minus 10.

We can say that 2 multiplied by 10 is equal to 3 multiplied by 10 minus or subtract 10.

And we know that 2 groups of 10 is equal to 20.

So now there are 20 sweets altogether.

Time to check your understanding.

Laura gives away a packet of sweets.

How many sweets are there altogether? So she started off with 5 packets of sweets, and she got rid of a packet of sweets.

So that's the image you need to be thinking about now.

Can you complete the two equations? Pause the video here.

Welcome back.

So we started off with 5 groups of 10, and we subtracted 10, one group of 10.

So we were left with 4 groups of 10.

So we can say that 4 groups of 10 is equal to 5 groups of 10 minus 10.

4 groups of 10 is equal to 40, and you may have skip counted in tens to find that.

Well done if that's what you've got.

Aisha returns to thinking about her table.

Remember her table is showing the multiples of 10 in order.

She's trying to find the next multiple of 10.

She knows that she needs to add 10 to 50 to find the next multiple of 10.

Remember when we're moving down that column, the product increases by 10.

She thinks about how she could write this as a multiplication equation.

So she can say that 60 has one more group of 10 than 50, and she can write 6 groups of 10 is equal to 5 groups of 10 plus 10.

6 groups of 10 is equal to 60.

So her multiplication equation says that 6 multiplied by 10 is equal to, is the same as, 5 multiplied by 10 plus 10.

Time to check your understanding.

Find the next multiple of 10 for 90.

Complete the equation.

Think carefully particularly about that equation bit.

Pause the video here.

Welcome back.

Well we know that to find the next multiple of 10 we can add 10.

So 90 plus 10 is equal to 100.

We've added a group of 10 to find 10 groups of 10.

So our equation is 10 groups of 10 is equal to 9 groups of 10 plus 10.

100 has one more group of 10 than 90.

So we can say that 10 multiplied by 10 is equal to 100.

Well done if that's what you got.

This time Aisha's thinking about the previous multiple of 10 in her table.

She wants to represent this previous multiple of 10 in a different way.

She knows that to find the previous multiple of 10, she needs to subtract 10 because when she moves up the column it decreases by 10.

So we know that 80 subtract 10 is equal to 70.

So we can say that 70 has one fewer group of 10 than 80.

But look carefully at the equations that she has written.

She has said 7 groups of 10 is equal to 8 groups of 10 minus 10.

7 groups of 10 is equal to 70.

So we can write that equation as equivalent.

7 groups of 10 is the same as 8 groups of 10 minus 10.

Time to check your understanding.

Find the previous multiple of 10 for 120.

Again, think really carefully about the equations that you can use to represent this.

Pause the video here and have a go.

Welcome back.

Hopefully you said that you could subtract 10 from 120 to find the previous multiple, which is 110.

We know that if we're going up the column we can subtract 10.

We can write the equation.

11 groups of 10 is equal to 12 groups of 10 subtract 10.

We knew 12 groups of 10 was 120, and we could subtract 10 from that to find 110, which is 11 groups of 10.

11 groups of 10 is equal to 110.

Aisha carries on thinking about adjacent multiples, but this time she plays a game.

She needs to connect the numbers in the circles with the previous and next multiples of 10, but oh no she's stuck.

She needs some help.

What advice would you give to Aisha to help her out? So we've got 3 multiples of 10 circled, 20, 40, and 30.

She needs to connect those with the previous, and next multiples of 10.

What can she do? I would remind her about what we know about previous, and next multiples of 10.

To find the previous multiple you need to subtract 10.

To find the next multiple, you need to add 10.

I think that would be some really good advice for Aisha.

If we know that, we can find the previous and next multiple of 10 for 40.

40 subtract 10 is 30.

That is the previous multiple of 10.

40 plus 10 is 50.

That is the next multiple of 10.

Great advice.

Time to check your understanding.

Complete the diagram to show the previous, and next multiple of 10 for 80.

Which numbers go in those circles? Is it A, B, or C? Pause the video and have a think.

Welcome back.

Did you remember that really useful advice we gave Aisha? To find the previous multiple of 10, we need to subtract 10.

80 subtract 10 is equal to 70.

To find the next multiple of 10 we need to add 10.

80 plus 10 is equal to 90.

So B is the correct option here, 70, 80, 90.

And we can use adding and subtracting a group of 10 to work that out.

Well done if you identified those.

Time for your second practise task.

In pairs, you're going to play a game.

You'll need a set of cards up to 12.

So the numbers 1 to 12 on cards or sticky notes.

Partner A is going to pick a card, and partner A will then multiply the number by 10.

Remember, you can skip count in tens to find the product if you need to.

Partner B is then going to identify the previous, and next multiple of 10.

Let's see how that works.

Aisha has picked the number 3.

So she's going to do 3 multiples by 10.

3 multiples by 10 is equal to 30.

Now she may have skip counted to find that, or she may just start to know that 3 multiplied by 10 is 30.

Laura is partner B.

Laura is going to identify the previous, and next multiple of 10 for 30.

So she says, "The previous multiple of 10 to 30 is 20.

The next multiple of 10 to 30 is 40." And she's absolutely right.

Aisha says, "Yep, that's correct." Well done Laura.

And then they can swap roles and take another turn.

For Question 2, I would like you to do two parts to this.

First of all, I'd like you to play Aisha's game, find the previous and next multiples of 10 to the numbers in the circles.

So 10, 50, 100 and 80 are circled.

Find the previous and next multiples of 10.

Then can you find any more adjacent multiples of 10? Be careful.

Some of those numbers in there are not multiples of 10.

Then for 10, 40, 80, and 90, can you complete the equations? So think about whether you're adding or subtracting groups of 10.

Good luck with those two tasks.

Pause the video here, and come back when you're ready for some feedback.

Welcome back.

How did you get on? I hope that you used our keywords a lot when you were thinking about the adjacent multiples.

So really thinking carefully about the previous, and next multiples of 10.

There are lots of ways you might have played the game.

Let's take a look at what Aisha and Laura did.

Aisha picked a 7 so she did 7 multiplied by 10 is equal to 70.

She may have skip counted, 10, 20, 30, 40, 50, 60, 70.

So remember we're now thinking about 70, and Laura's challenge is to find the previous, and next multiple of 10 for 70.

I wonder if she got it right.

Let's take a look.

She said, "The previous multiple is 60, and the next multiple is 80." What do you think? Do you agree? She's absolutely correct, and Aisha said, "Yep, that's correct, well done." Hopefully you have lots of opportunities to think about lots of different multiples of 10.

For Question 2, remember if we want to find the next multiple of 10, we need to add 10, and if we want to find the previous multiple of 10, we can subtract 10.

Let's take a closer look at 50.

50 plus 10 is 60, so the next multiple of 10 for 50 is 60.

50 subtract 10 is 40, so the previous multiple of 10 is 40.

You may have noticed that we found some other previous and next multiples.

We found the multiples for 40.

10 more than 40 is 50, and 10 less than 40 is 30.

30 and 50 are the previous and next multiples for 40.

And then let's take a closer look at some of these equations.

10.

What is 10 equal to? Well, 10 is the same as no groups of 10 plus 10.

So we could say that 10 is equal to 0 multiplied by 10 plus 10.

We could also think about the previous multiple.

Two groups of 10 minus 10 is equal to 10.

For 40, 3 groups of 10 plus 10 gives you 40, or 5 groups of 10, which is 50 minus 10, gives you 40 as well.

Take a closer look at those last two pairs of equations to make sure you completed them correctly.

We have come to the end of our lesson where we've been explaining the relationship between adjacent multiples of 10.

To summarise our learning, we've learned that adjacent multiples of 10 have a difference of 10.

So we can say that 10 more than 40 is 50, and 50 is the next multiple of 10 to 40.

We can also say that 10 less than 40 is 30, and we can say that the previous multiple of 10 for 40 is 30.

Thank you so much for all of your hard work in this lesson today and I look forward to seeing you in another lesson soon.