Lesson video

Hello, I'm Ms. 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 today's lesson, you'll be able to divide a two-digit by a one-digit number using short division where there's no regrouping or remainders involved.

When I was younger, I was taught short division as something known as the bus stop method.

Was one of the first methods my parents taught me when it came to division, but sometimes I forgot how to use it, and also I didn't really understand why I was doing what I was doing.

So today, it is my job to teach you how to use short division, and to learn all about why we do what we do when using short division.

So these are your keywords for this lesson, and I'd like you to repeat them after me.

Short division.

Dividend.

Divisor.

Quotient.

Good job.

Let's move on.

Short division is a formal method of division often used when dividing any number by a one-digit number.

The dividend is the amount that you want to divide up.

A divisor is a number that divides the integer exactly, no remainder.

A quotient is the result after division has taken place.

For your first lesson cycle, we are going to be understanding short division and how to lay it out, how to arrange it, and how to use it.

So 63 glow sticks are shared equally between three children.

How many glow sticks does each child get? I want you to think about what division equation is needed.

So our division equation is 63 divided by 3.

63 is our dividend.

That is the number that we are dividing up.

3 is our divisor, and we're calculating the quotient.

Today, you will be exploring how to calculate using short division.

In order to represent this, we're going to use our glow stick bundles that we've got here.

Now, do remember one bundle is equivalent to 10 glow sticks, and we're going to be sharing this amongst three children.

So the first thing that we need to do is write the divisor and dividend.

When it comes to arranging short division, the divisor goes outside the division frame, and the dividend goes inside.

So you can see here that the divisor, 3, is placed outside the division frame, and 63 is placed inside.

It's also very important because I know this is on the computer screen, but when you are actually writing this down, that you leave a space between your dividend, and it's good practise to do so, and this is because, eventually, when there are instances of regrouping, you're going to need that space to write the regrouped amount.

So it's always a good habit to make sure that you've got space in between your dividend.

So the dividend is always placed inside, and the divisor is always placed to the left and outside.

Next, you're going to start by dividing your tens, and we're actually working from the left.

6 tens divided by 3 is equal to 2 tens, and you write the 2 above the 6 tens.

Now, you're going to divide your ones.

3 ones divided by 3 is one one, and you write the one one above the 3.

So the quotient is always written above.

So each child gets 21 glow sticks.

So Andeep used place value counters to help him solve this equation, and I'm going to show you how this can be represented with that as well.

We can change our 6 into 6 tens using our place value counters, and the same for our 3 ones, and we can see that 6 tens divided by 3 is equal to two groups of 3 tens, and that our one ones, our 3 ones divided by three, gives us one group of 3 ones.

So each child ends up getting 21 glow sticks.

And always remember the quotient is written above.

Have a look at this table.

We've got short division.

I want you to think about what you notice.

So you may have thought about these points.

The dividend is always placed inside, the divisor is always placed to the left, and the quotient is written at the top.

However, unlike addition, subtraction, and multiplication, here, you work left to right.

Over to you.

I'd like you to label the short division below.

You can pause the video here, and when you're ready to join us, just click play.

So how did you do? So you should have gotten 3 as your divisor because that is the number that we're dividing by, 99 as your dividend because that is the number that we are dividing up, and 33 as your quotient because that is the answer in the division equation.

So 48 sweets are shared between 4 children.

How many sweets does each child get? So in the cup, there are 10 sweets.

48 is our dividend, and I know I'm dividing because the question says shared, and it's between 4 children, so 4 must be my divisor.

So the equation that I'm calculating is 48 divided by 4.

So first, again, what we're going to do is write the dividend and the divisor.

So the divisor goes outside, the 4 goes outside, and the dividend is written inside with spaces.

Then, we're going to divide our tens first.

So 4 tens divided by 4 is 1 ten, and remember to place the one on top.

Then, you're going to move on to dividing your ones.

8 ones divided by 4 is equal to 2 ones.

So each child gets 12 sweets each.

So here's Andeep's calculation for the division question, 36 divided by 3.

He says that he knows 3 groups of 12 is 36.

3 multiplied by 12 is equal to 36.

36 can be divided into 3 groups, which is 12, so 36 divided by 3 is 12.

In this case, mental strategies are more efficient than using short division because you should know your times tables facts.

You can use the inverse to help you.

And remember, the inverse means the opposite.

So if you know 3 multiplied by 12 is 36, then you also know that 36 divided by 12 is 3.

So using Andeep's calculation, you can complete Izzy's calculation.

So 36 is our dividend.

Our divisor is 3.

We know that 12 must be the quotient.

Right, I'd like you to select the correct short division for this equation.

So 36 divided by 2 is 18.

You can pause the video here.

How did you do? So C is the correct answer because 36, the dividend, is placed inside.

The divisor is 2, and it is placed to the left.

The quotient is 18, and it is written at the top.

Onto your task.

For Task A, question one, you're going to be filling in the blanks.

You've got different representations there, and I'd like you to use those to fill in the gaps.

Question two, you're going to be matching the equation with the correct short division, and you're also going to be filling in the gaps.

You can pause the video here.

Off you go.

Good luck.

So how did you do? For question one, you should have got this.

You can pause the video here to mark your work, and then when you're ready, click play to carry on.

Right, let's have a look at question two.

So if I have a look at the first box, so 63 divided by something, which was equal to 21.

Well, if we look across to the right, we can see that 3 was the divisor because it was placed outside the division frame to the left.

So ultimately, 3 would've been the missing number in that equation.

Let's look at 55 divided by 5.

This time, the quotient was missing, but if we look to the right, the quotient was placed at the top, and that is 11, so 11 would've been the missing number in your division equation.

We're dividing by 5, so that means our 5 is the divisor.

And lastly, 88 is the dividend, and that is because it is placed inside the division frame.

Onto our second part of this lesson.

This time, using everything we've learned, we're now going to use short division and apply it.

96 marbles are shared equally between 3 children.

How many marbles does each child get? So what division equation do you think is needed to calculate this equation? 96 is the dividend 'cause that is the amount we want to divide up.

3 is the divisor.

This is the number we are dividing by.

The quotient is what we're looking for.

So we're going to begin by writing the divisor and dividend into our division Frame.

3 goes outside because it's the divisor.

The dividend is 96.

It is placed inside with enough space.

You are to start off from the left, and dividing the tens.

You can make three groups of 3 tens from 9 tens in the dividend.

So 9 tens divided by 3 is equal to 3 tens, so you place the 3 at the top.

Now, you're going to move on to your ones, and you're going to divide your ones.

You can make two groups of 3 ones from 6 ones in the dividend.

6 ones divided by 3 is 2 ones.

So that means each child will get 32 marbles each.

Over to you.

You're going to select the correct division equation for this equation.

66 marbles are shared equally between 3 children.

How many marbles does each child get? Please pause the video here and have a think.

So how did you do? B is the correct answer, and that is because 66 is the dividend.

It is the number that we are dividing up.

3 is the divisor.

That is the number that we are dividing by.

Back to you again.

This time, I'd like you to select the correct short division for this equation.

82 marbles are shared equally between 2 children.

How many marbles does each child get? You can pause the video here.

So how did you do? B is the correct answer.

The dividend is 82.

This is placed inside.

The divisor is 2, and that's placed to the left.

I love these questions because it makes you think just that little bit harder.

A square has a total perimeter of 88 centimetres.

What is the length of one side? So the most important part here, I would argue, is actually finding out what the division equation is.

So what do you think it is? Well, I know that a square has four equal sides, and the perimeter is 88 centimetres, so 88 must be my dividend.

My divisor is 4.

I need to figure out what the length is of one side.

So we're going to begin by writing the divisor and dividend.

The 88 goes inside because that is the dividend, and the divisor is 4, so it's placed outside to the left.

Next, you're going to start off by dividing the tens.

You can make two groups of 4 tens from the 8 tens in the dividend.

So that is the same as saying 8 tens divided by 4 is equal to 2 tens.

You place that at the top.

And then, you've guessed it, we move on to our ones.

You can make two groups of 4 ones from the 8 ones in the dividend.

So 8 ones divided by 4 is 2 ones.

You would've known that because if you know that 8 tens divided by 4 is 2 tens, then you know that 8 ones divided by 4 is 2 ones.

We've scaled down by 10.

Which means that the length of one side is 22 centimetres.

Over to you.

So you're going to select the correct short division for this question.

An equilateral triangle has a total perimeter of 39 centimetres.

What is the length of one side? Pause the video here to have a think.

So what did you get? Let's have a look.

You should've got C.

The dividend is 39 because this is the total perimeter, and the divisor is 3 because you need to calculate the length of one side.

So onto the main task.

For question one, you're going to be using short division to answer the problems below.

1a, 63 sweets are shared between 3 children.

How many sweets does each child get? Question 1b, 86 marbles are equally shared between 2 jars.

How many marbles are in each jar? And question 1c, 93 cards are shared equally between 3 children.

How many cards does each child get? For question two, you're going to use short division to solve these problems. An equilateral triangle has a total perimeter of 39 centimetres.

What is the length of one side? And for 2b, the total perimeter of two squares is 88 centimetres.

What is the length of one side? You can pause the video here.

Off you go.

Good luck.

So how did you do? For question 1a, you should have got 21 as your quotient, so each child gets 21 sweets.

For question B, you should have got 43 as your quotient.

And for question C, you should have got 31 as your quotient.

And what you may have noticed is because the digits in the dividend are multiples of the divisor, it should have been relatively quick.

But again, it makes for good practise.

Let's look at this question in depth.

So for 2a, we know that an equilateral triangle has three sides, and what I would've done first, figure out what is the division equation that we are calculating.

So in this case, 39 is the dividend, the divisor is 3, and then you would've had to make sure that you placed 39 inside the division frame with the divisor being outside.

So we know that we can make one group of 3 tens from the 3 tens in the dividend.

We can make three groups of 3 ones from the 9 ones in the dividend, which is 3.

So our quotient was 13.

For 2b, the total perimeter of two squares is 88.

What is the length of one side? So what we need to do first is calculate what the perimeter of one square is.

We know that two squares is 88, so one square, what we'd have to do is halve it.

That could've been a good mental strategy that we used.

But because we're using short division, we need to, our dividend is 88, and our divisor is 2, because there are two squares.

We need to figure out the perimeter of one square.

So 88 divided by 2 would've given you a quotient of 44.

Now that we've found out the perimeter of one square, we need to find out what the length of one side is.

So our dividend this time is 44, and our divisor is 4.

44 divided by 4 gives us a quotient of 11.

So the length of one side is 11 centimetres.

If you got that correct, give yourself a tick.

Well done.

So to summarise today, what we did was divide a two-digit by a one-digit number using short division, which included no regrouping or remainders.

So hopefully, by the end of this lesson, you can use short division to organise division by partitioning.

You can also identify the similarities between the representations of division and short division.

And lastly, understand that partial quotients are recorded above the dividend in the correct place value columns.

I hope you enjoyed this lesson.

I hope by breaking this down further, you now understand what short division is and how to use it.