Lesson video

Hello, I'm Miss Miah, and I'm so excited to be a part of your learning journey today.

I hope you enjoy this lesson as much as I do.

In this lesson, you'll be able to explain the relationship between adjacent multiples of eight.

Your keywords are on the screen now, and these are adjacent and multiple.

I'd like you to repeat them after me.

Adjacent, multiple.

Fabulous.

Let's move on.

So adjacent means next to each other.

A multiple is the result of multiplying a number by another whole number.

And these are two keywords that you will see popping up in this lesson.

This lesson is all about representing and counting in eights as the eight-times table.

And we have two cycles here.

The first cycle is about adjacent multiples of eight.

Now remember, adjacent means next to.

So what I want you to think about is what do you think are the adjacent multiples of eight? So if I said 16 is a multiple of eight, what do you think that adjacent multiples would be? And in the second lesson cycle, we will be solving problems using our knowledge of the adjacent multiples of eight.

I'm really excited about this lesson, so let's get cracking.

In this lesson, you'll meet Andeep and Izzy.

Andeep writes multiples of eight in order and looks at adjacent numbers, numbers that are next to each other.

What patterns do you notice? Adjacent multiples have a difference of eight.

When moving down the column, the product increases by eight.

When moving up the column, the product decreases by eight.

So have a look at the table.

I would like you to tell me what the adjacent multiple is.

You can pause the video here.

So what did you get? 48 is the answer, and that's because we've added eight to 40.

Back to you.

Pause the video here to fill in the gap.

So what did you get? 56 is the correct answer.

Now adjacent multiples can also be represented on a number line, and you can see that on the screen now.

Adjacent multiples of eight are zero and 16.

So you can see that zero is an adjacent multiple of eight, we've subtracted eight, and to get from eight to 16, we've added eight.

So the adjacent multiples of 80 are? Back to you.

You can pause the video here, have a go.

So what did you get? You should have got 72 and 88.

You would've got 72 by subtracting eight from 80, and you would've got 88 by adding eight to 80.

Back to you again, I'd like you to fill in the blank.

So how did you do? You should have got 40, and that's because you are adding eight to 32.

You can record an adjacent multiple using a mixed-operation equation.

And this is how you do that.

You know that one group of eight is eight, so eight equals one times eight.

16 is one group of eight, add eight, so 16 equals one times eight add eight.

Two times eight is equal to one times eight, add eight.

And that's your mixed-operation equation.

So let's now have a look at 24.

We know that three groups of eight is equal to 24.

Now if we then subtract eight, we end up with our adjacent multiple of 16.

16 is three groups of eight, subtract eight.

So 16 equals three groups of eight, subtract eight.

And if we were to record this as a mixed operation, we could write two times eight is equal to three times eight takeaway eight.

Adjacent multiples can also be represented on a number line.

40 add eight is 48.

You can write this as six times eight equals five times eight add eight, and 48 is equal to five groups of eight add eight.

Now let's have a look at what happens when our adjacent multiple is 80.

So we know that 10 times eight is equal to 11 times eight take away eight.

So 80 is equal to 11 groups of eight, subtract eight.

Back to you.

You're going to be completing the equation.

You can pause the video here.

So what did you get? Well, we're going from 64 to 56, and we've subtracted eight.

So if we know that 64 is eight times eight, we've subtracted eight, and then we end up with 56, so that should have been your equation.

If you got that, well done.

So your task for lesson cycle one.

For question one, you are going to be finding the missing multiples.

For question two, you're going to find the missing adjacent multiples, and then you're going to complete the mixed operation equations.

Remember to use what you know and your table facts of the eight times tables to help you.

And then, for 2B, you're going to write your own.

So, for example, 48 to 56.

So 56 is equal to six times eight add four.

Are there any other equations that you can write based on the eight times tables? You can pause the video here, click play when you're ready to rejoin us.

So how did you do? Let's have a look at question one.

I'm going to count on from zero all the way up to 96.

You can mark your work whilst I do that.

So, zero, eight, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96.

Question two, you are going to find the missing adjacent multiples and complete the equations.

So you've got eight, 16.

So in this case, 16 is the multiple, and that is equal to one times eight add eight, so eight was your missing number.

Let's have a look at 16 to 24.

So 24 is equal to two times eight add eight.

And then, 32 to 40, 40 is equal to four times eight, add a group of eight.

And for your own example, so for example, I'm going to choose 40 and I'm going to say that is equal to four times eight add eight, or I may have used subtraction and I may have picked 64.

I would've written 64 is equal to nine times eight, takeaway eight.

If you've got all of those answers correct, well done, give yourself a tick.

Let's move on.

So for this lesson cycle, we're now going to be solving problems using what we know about the adjacent multiples of eight.

Let's get cracking.

Now, Andeep has filled out the eight times tables using knowledge of the twos, fours, five and 10 times tables.

Now because of this, Andeep only needs to calculate seven more facts to complete his eight times tables.

I love this because it means we can figure out so much more using what we know, and in this case, it's our tables facts.

So I really want you to think about your knowledge of the twos, fours, fives, and 10 times tables as well for this part.

Now, in order to help us find a missing fact using what we know, we can actually use an array to help us.

So Andeep says that he knows two times eight is 16.

If he knows that, then he also knows three times eight is basically two times eight, and then you're adding on another eight.

So here, we can represent that using an array.

So two groups of eight is 16, and 16 equals two times eight.

And then we've added on another group of eight, and that gives us our answer, which is 24.

Now you can use an array to represent finding the missing facts.

So if five times eight is 40, then you also know that if you add on another group of eight, that will give you 48.

Over to you.

I'd like you to draw an array to calculate what three times eight is.

Andeep's given a hint here if you.

If you know that two times eight is 16, how can you use this fact to help you? You can pause the video here, and when you're ready to rejoin us, click play.

So how did you do? Well, two times eight add eight would've given you 24.

Now Izzy says that if she knows that 12 times eight is 96, then she also knows that 13 times eight is 104.

Is she right, and can you prove it? Well, using what we know about adjacent multiples, Izzy is correct because she has added eight more to 96 to find the adjacent multiple.

Eight add 96 or 96 add eight gives us 104, and you can see that that's been presented in the array.

It's another group of eight, so she's correct.

Back to you.

If Izzy knows that 13 times eight is 104, then she also knows that 14 times eight is 112.

Do you agree? Explain how you know to your partner.

So you may have discussed that she is correct because she has added eight more to 104 to find the next adjacent multiple of eight.

Right, let's have a look at this.

Six times eight.

If Andeep knows that five times eight is 40, then he'll just add on one more group and he got 46.

So I wonder what happened there.

Now, so Andeep is saying that if he knows that five times eight is 40, then he'll just add one more group and he will get 46.

Andeep has used an array to calculate six times eight.

Is he correct? Andeep is incorrect because he has added one more group of six when actually he should have added one more group of eight to find the adjacent multiple.

So that's what he should have done.

Back to you.

Which is the correct array for seven times eight? I'd like you to justify your thinking to your partner.

You can pause the video here.

So how did you do? A is correct because you need to add one more group of eight to find the adjacent multiple.

Now you can compare adjacent multiples using knowledge of groups.

I know that two times eight is greater than one times eight.

How? So let's have a look at the arrays.

That's one group of eight, and immediately you can see a difference there.

So that means one times eight is less than two times eight.

So in this case, four times eight is greater than two times eight.

And you can see that because there's two more groups of eight as compared to the two groups of eight that you see on the right-hand side.

So which is greater? Back to you.

You can pause the video here.

So how did you do? Well, seven times eight is greater than six times eight because it has one more group of eight.

You can compare adjacent multiples using knowledge of groups.

Now, in this case, there's a bit of a difference here.

We've got a mixed operation equation that we are comparing to a multiplication equation, and we can see here that you've got three times eight add eight, which, in other words, represents four times eight.

So that means three times eight add eight is greater than three times eight.

And we can see that visually because it's been represented by the array.

There's one more group of eight.

Back to you.

Which is greater, and I'd like you to justify how you know to your partner.

You could pause the video here.

So how did you do? Four times eight add eight is greater than four times eight because it has one more group of eight.

Okay, so onto your main task for this lesson cycle.

For question one, you are going to be using what you know to build up the table's facts.

So now this is your chance to show off what you know about your twos, fives, tens, and four times tables to help you.

But don't forget to use your knowledge now of adjacent multiples of eight to figure out the rest of the facts.

And for question two, you're going to be using the inequalities symbols to fill in the missing symbols.

You can pause the video here to have a go at the task.

Click play to rejoin us when you're ready.

So how did you do? Let's have a look.

So for question one, I'm going to read out the answers, and I would like you to tick them as you go along.

And I'll also be providing a quick explanation as to how you may have calculated that answer.

So let's start off with zero times eight.

Zero times eight is zero, one times eight is eight, two eights are 16, three times eight is 24.

So what you could have done here is added eight to 16 to get that multiple.

Then you would've added eight to 24 to get your next multiple, which is 32.

Now you know your five times table, so five times eight is 40, and then to 40 you would've added eight to get 48, and then to 48 you would've added another eight to get 56, and that's seven times eight.

And then to seven times eight, you would've added eight to 56 to get 64.

Nine times eight is 72, so you would've added eight to 64 again as well.

Or if you knew that 10 times eight is 80, you could have subtracted eight to get 72.

And to get 88, you could have added eight to 80 to get that multiple there.

And then you would've added eight to 88 to get 96.

Let's move on.

You can pause the video here now to mark your work, and then I'll go through some of the examples in the right-hand column in far more detail as to why those are the answers.

So pause the video here.

Okay, so now that you've marked your work, let's have a look at three times eight add eight is greater than three times eight, and that is on the right-hand side column as the second one down.

So we know that that is greater because three times eight, and if you're adding another group of eight, means that it will be greater than three times eight.

If we look at the next question, six times eight is equal to five times eight add eight, because by adding that extra group of eight, we end up with the same amount of groups of eight, so that would be six times eight.

Next.

Seven times eight is less than seven times eight add eight.

And that's because seven times eight add eight, we've added an extra group of eight, which means that our multiplication equation now would be eight times eight.

And lastly, nine times eight is equal to 10 times eight take away eight because by taking away a group of eight, end up with nine groups of eight.

And that is the end of the lesson.

I really hope you enjoyed that lesson as much as I did.

We're now going to summarise our learning.

So in this lesson, you are able to explain the relationship between adjacent multiples of eight.

You hopefully now understand that adjacent multiples of eight have a difference of eight, and if you add eight to a multiple of eight, you get the next multiple of eight.

You also understand that if you subtract eight from a multiple of eight, you get the previous multiple of eight.

I really hope that you enjoyed this lesson, and I look forward to seeing you in the next one.