Lesson video

Hello, and welcome back.

My name is Mrs. Burns, and I'm going to be your teacher for today.

This is lesson 18.

Have you got a pen, pencil, something to write on.

If you haven't, you're going to need those today.

So pause the video and go and find them and I'll see shortly.

Welcome back.

We're going to begin by looking at what happened last lesson.

Mrs. Sawyer, last lesson taught you about how the length of one part can help you find the length of the whole.

She used lots of different examples and she left you with this practise activity.

Did you have a go? If you've got it with you, Fantastic.

If you haven't, don't worry.

We're going to go through how I solved it.

Let's read it together.

Hannah has cut her two ribbons into quarters.

We can see a quarter of each ribbon below.

Which colour of ribbon was the longest to start with? Now in math, we often look at what's the same.

What's different.

Can you see the fraction is the same? Well, the question told us that as well.

We've got one quarter of each piece of ribbon, but what's different? Can you see? The length of the pieces are different.

The red ribbon it's quarter, it's longer.

So that makes me think that the red ribbon is going to be longer.

So let's see if I'm right.

I used our STEM sentence to help me work it out.

I know I've got a quarter, so that helped me.

If one quarter is apart the whole is four times as much.

Then I look at that four, the four was the denominator on the fraction.

Can you see? The four shows the whole world is split into four equal parts.

So my second STEM sentence just really make sure we've grasped that.

Take four parts and put them together to make one whole.

Watch how I can show you with my screen.

I've got one quarter of the red ribbon.

Here's another one quarter another one quarter, another one quarter.

I haven't added four more.

I've got four equal parts all together and I can do the same with the blue.

One quarter blue, another one quarter, another one quarter, another one quarter.

Now, if you drawn it and your equal parts, aren't exactly the same.

Don't worry.

You were just having a go.

And that's the main thing.

We try to draw them as accurately as we can to show there are equal parts.

And now when I compare them, I can see that the red is longer because each of the equal parts is longer.

So when I put them together I can say, so if you sat, the red ribbon was longer.

Well done.

Today we're looking at slightly different questions.

Take in one more small step in our journey of fractions.

Look at this question.

Beth has some smarties.

This picture shows a one fifth of the amount of smarties she has.

How many does she have in total? Now what we've changed isn't the fraction each time.

It's the amount.

Can you see, it's not the length of the part.

It's the amount inside that part.

So instead of showing you the length of one fifth, I've shown you what one fifth is with the amount.

I've got three smarties in that one fifth.

Can you visualise what the whole would look like? Pause the video and have a little go.

You could draw the smarties, or if you're used to drawing a bar model, have a ago.

Pause the video.

So I'm going to show you how I worked it out.

This is Beth's one fifth, using our STEM sentence again, we know we have one fifth, one fifth is apart.

So look at that denominator.

Which shows us designate one fifth is the part.

Then the whole is five times as much.

And just to be sure here's our second STEM ssentence to really help us grasp this.

If it's five times as much, how many parts will that be in total? Again, look at the denominator.

The number on the bottom of the fraction, the five it shows us a whole is split into five equal parts.

So let's read that STEM sentence together.

Take five parts and put them together to make one whole let me show you how this looks.

One fifth or we knew that, that was in our original picture but I need five of them all together.

So here's another one and another one and another one and and another one.

Just count, make sure I've got five.

Good,right? So that is a bar model.

It helps us represent what we're thinking.

If you're not used to them, don't worry.

They're just meant to help us understand what a whole looks like.

And I can see my five equal parts bailed at my whole but it doesn't tell me exactly how many there are.

I still have to do a bit more thinking.

I need to look at each part.

Each part has how many sweets? Count them, that's right.

Three sweets.

So I could go and count them all.

One, two, three four, that.

No Mrs. Burns, we need to use the skills we have.

Remember your multiplication facts.

It's much quicker to multiply than to add.

So we're going to look at our five equal parts.

Each of our five equal parts has three smarties.

So what multiplication fact would that be? Tell me.

Well done.

You're right to work out all together.

We need to do five times three smarties, 15 smarties.

I asked you to have a go at drawing it to this start.

Did you have 15 smarties on your page? Well done.

So now let's look at max? Max has some smarties.

This picture shows one one third of the amount of smarties he has.

How many does he have in total? Just have a think.

What's the same.

What's different? The best smarties.

Pause the video, Jot something down or tell someone.

Okay.

Did you see that the amount of smarties was the same? We still have three but this time the fraction is different.

I've got one third.

I'm going to use my STEM sentence to help me.

If one is the part, the whole is times as much.

Can you have a go at working this out before I share how I worked it out.

Pause the video and have a ago.

So let's have a look at how I worked it out.

I've got one third of Max's smarties.

So did you realise that one third is the part? And again, if one third that's the three, I need the whole to be three times as much.

Let's read that STEM sentence together.

If one third is the part, the whole is three times as much.

So what would that look like, my whole? How many parts would it have? Okay.

You all pick, try and check.

Yes.

If the denominator is three, we know a whole has to be made up of three equal parts.

So look at my second STEM sentence that, let's say it together.

Take three parts and put them together to make one whole.

Have drawn a bar model again.

Look.

Here's one part.

We know that's one third.

He's another one third.

And another one third, just check them right.

I've got three equal parts.

Brilliant.

So to find out how many there are all together, after I looked at each equal part, each part.

I thought he told me this.

Tell me again, printed in three sweets.

Each part has three sweets.

Can you tell me what multiplication factor which you use? Yes, well done.

All together that would be three times three smarties, which equals nine smarties altogether.

Your packet your picture from the start.

Did you have max with nine smarties? Brilliant.

Now we're changing it slightly.

We're going to compare different people's smarties.

This time we've got Ahmed and Sally's before we go any further, we like to think what's the same, what's different? Pause the video, jot down or tell someone, your Teddy, the person with you or tell a screen.

What's the same, what's different.

Pause.

Okay.

Did you have a look? What's the same? Now in this question, they both have the same amount.

Can you see how many smarties? Yes.

Well done, five.

But what's different? The fraction, Ahmed had a half.

Sally has a quarter.

Now can you visualise what the wholes would look like? Cause that's my question.

Who will have the most smarties? I'd like you to pause the video and see if you can have a go at drawing what it would look like.

You can either draw the smarties or try drawing a bar model to represent the whole.

Pause the video and have a go.

Okay.

Let's see how I solved it.

I used my STEM sentence again.

If one is a part, the whole list times as much.

So I need to look at Ahmed first.

In fact bad has one half is a part then the whole is two times as many.

And I use my denominator, the two to help me because again, I know that if you've got a two phase denominator I need two equal parts.

So my second STEM sentence take two parts and put them together to make one whole.

Let's have a look at how it looks in my bar model.

Here's my one half, there is my other half.

So I know that Ahmed's whole has two equal parts.

What do you think the calculation will be? Can you tell me? Thank you.

I can see that Ahmed has two times five smarties But with 10 smarties all together.

Now let's compare that to Sally.

Remember her fraction was different.

So I've emptied my STEM sentence.

Now look at the bottom again.

I'm not going to fill in the parts.

Can we say it together? And I'm going to leave a blank for you to say each of the missing gaps.

If one is a part and the whole is times as many, take parts and put them together to make one whole.

So how many parts does Sally need? Well done.

Four equal parts and look at the denominator.

The denominator shows us.

So let's have a look at Sally's , one part, another equal part, another equal part, another equal part.

So what multiplication factor we need? Can you tell me? Well done.

Four equal parts.

Each with five sweets.

Sally has four times five smarties, 20 altogether.

That's all working out but we still haven't answered the question.

Who will have the most smarties? So who has the most smarties? Yes, we'll have 10, Sally.

And we know that because 20 is greater than 10.

Well done.

For our last example, we're going to compare two classes.

I've got class A and class B.

And I'm going to ask you what's the same, what's different again.

That's a really good question to ask yourself at the start of any problem.

So let's have a look.

Pause the video.

See what's the same.

What's different.

Okay.

So, did you see that the amount was the same, I can see four children in both classes.

But what's different? Yes.

The fraction.

We can see one fifth of class A and one sixth of class B.

So think about the skills you've used today.

Think about the STEM sentences.

Can you predict which class will have the most? Why? Pause the video and see if you can draw either of the classes using the people.

Or draw using a bar model.

Pause the video.

Welcome back.

I use the STEM sentences to help me.

If one is a part, the whole is times as many, and take parts and put them together to make one whole.

Let's see how I did that.

So let me show you how I worked it out.

I started with class A and I use those STEM sentences.

I can say there's one fifth and here's the 10 nominated at the bottom to help me find my total number of parts.

Read the STEM sentences with me.

If one fifth is apart, then the whole is five times as much.

So I need to take five parts and put them together to make one whole.

I've drawn a bar model different this time.

Watch, here I go, one part, two parts, three parts four parts, five parts after a workout might whole.

I need to know how many are in each part.

How many are there any each part? look at the picture.

` There are four students, well done.

So I now need to put four in each of my parts.

So this is a bar model with numbers.

This helps us visualise our calculation really easily.

Five parts with four in each part.

So what multiplication factor will that be? Yes of course.

Well done.

Five times four equals 20 students.

There are 20 students in this class.

Now let's look at class B, use the STEM sentences again.

If one six is a part then whole is six times as much, take six parts and put them together to make one whole.

So heres my parts, watch one two, three, four, five, six, six equal parts.

Each is with one six.

But I need to look at each part before I can work out the total whole class.

Each part has how many? Yes, of course.

Four, the picture shows us and we knew that they were the same.

So I put four in each of my parts.

Now can you see the calculation? I've got six parts each with four.

Of course, it is well done.

Six times four is 24 students.

That's my favourite times table.

I think it's got a really nice ring to it.

Six times four is 24.

It's also my birthday.

I was born on the 24th.

So I liked that number and it's a special time saver for me.

Always been my favourite.

You got a favourite times table.

Anyway, I haven't answered the question, have I? Which class has the most? Well of course, Well done.

It's class B because 24 is greater than 20.

Well done.

That's the end of our lesson now, but before we go, I'm going to set you a practise activity to have a go at.

Which class has more students, class C or class D.

So have a think.

What's the same? What's different? Can you draw a bar model to help you piece together the whole.

Can you use our STEM sentences? I'm going to be with you in the next lesson.

So when you next log in, I will share my workings out with you, remember to bring yours too.

Thank you.

I hope you have a lovely day.

Bye-bye.