Short division (Part 3)

Key Stage 2

Maths

Multiplication and division

﻿Hello, my name is Miss Thomas I'll be going through the lesson with you today. We're doing a lesson on Short Division today using the Short Division Method. So let's get started with our lessons learning. In today's lesson agenda first, we'll be using the short division method, including zero as a place value holder. Then we'll go to a let's explore task, where you can practise. After that we'll be finding multiples of three digit numbers. And finally we'll finish with the end of lesson quiz, where you can test yourself on the learning. The equipment you're going to need for this lesson is a pencil, paper and a ruler, pause the video now if you need to gather your equipment. Here we have a word problem. A ranger is placing birdhouses on trees in the forest. Each tree can have six bird houses attached to it. If the ranger has to place 138 bird houses, how many trees will he use? The first question is, what is known? And what is unknown? Pause the video and explain out loud what is known and what is unknown. Welcome back, you might've found that we know that the ranger has to place 138 birds houses, and that we know that there are six bird houses attached to it, to each tree. What we want to know, is how many trees the ranger's going to need to use. So the next question is, how might you solve this problem? Pause the video and explain out loud to your screen. Welcome back. You might've found that we need to do 138 divided by six, to find how many trees the ranger will need to use for his bird houses. We've got some star words, the first is my turn dividend, your turn. Dividend is the number being divided. So in our calculation, the dividend is 138. The next star word is my turn, divisor your turn. Divisor is the number the dividend is being divided by. So in our calculation, we're dividing by six, the divisor is six. The next and final word is my turn, quotient your turn. The quotient is the result. That's the missing value we're trying to find. So now let's help the ranger. We're going to do 138 divided by six, on one side I've got my place value chart where I'm going to divide 138 by six using counters. And on the other side, I've got my bus stop, where I'm going to use short division written method to solve the same equation. You are going to have your turn in a minute in the let's explore tasks so watch carefully. Okay, so in my written method, I've got 138 is my dividend that goes on the inside, that's the number that I'm dividing. And I've got six on the outside. Remind me, what was the name of the six? What do we call it in the short division method? Great it's our divisor. And what is a divisor? Fabulous, the number that we're dividing it by. And our missing part is our quotient. What is a quotient? Great, the quotient is our result and that goes on the top line, of our short division algorithm. Okay so let's get started with our counters. I've got the number 138, so I need one hundreds counter three tens and eight ones. Our divisor is six, so we're dividing by six, I'm grouping my counters into groups of six. If I've got 100, I can't group that into groups of six so, I'm going to add a zero on top of my written method because I cannot divide it by six, doesn't divide equally, and there are no groups of six. So then, my one group of a hundred becomes 10 tens because 100 is equal to 10 tens, so I'm going to regroup it, to my tens column. So now, I've regrouped my 10 tens I now have 13 tens in my tens column. So how many groups of six can I have in the 13 tens? Let's have a look I've got one group of six, two groups of six and 13 tens. But I've got one group of 10 that I couldn't share equally so we've got two groups of six sorry, that we could share equally. And one 10 that wasn't divisible by six. So then I'm going to regroup that one 10, into 10 ones. So now, we've got 18 ones in our ones column, how many groups of six can we have on 18 ones? We've got, one group of six, two groups of six, three groups of six. 18 divided by six is equal to three, there are three groups of six in 18. So our quotient oh look at that I've got a zero there, in my hundreds column so how would I read that number? What do you think? Call out your answer. Great, that zero is not holding the place value so we would read it as 23, my quotient is 23. 138 divided by six is equal to 23. Now you've reached the let's explore task, solve the following equation using the short division method to practise. Use the star words to help you. Pause the video to complete your let's explore task. Let's take a look at the answers, we'll go through it together and I'm going to ask you to call out some of your thinking. So the equation was 2,736 divided by six, which number is my dividend? 2,736, is my dividend. And what is the dividend? Call out your answer. Great, the number that's being divided. So now we know that six is our divisor, what is a divisor? Great, the number that you're dividing by. So when we're dividing, we're going to be dividing into groups of six, okay? And our quotient, our result is going to go on the top of our written method. So, when we're doing short division, which column do we start with? The one with the lesser value, or the greatest value? Brilliant, the greatest value and which one here has the greatest value? What's the highest value column we have here? Our thousands column. And we've got two thousands. So, I want to group 2000 into a group of six, I've got two thousands, I can't group it into a group of six. So I'm going to put a zero, and I'm going to regroup my two thousands into 20 hundreds. So now in my hundreds column, how many hundreds have you got there now? Call out your answer. Brilliant you've got 27 hundreds. So now we want to group our 27 hundreds into groups of six. Well, I know that I could group it into four groups equally because six times four is 24, but that I'm going to have a remainder 24, 25, 26, 27, I had 27 hundreds, so that's three hundreds that I can't share equally. What must I do? Pause the video and explain to your screen what I must do. Great, we need to regroup them into our tens column, so our three remaining become 30 tens. So now we have 33 tens in our tens column. Can we group 33 tens into six? Well, I know that six times five is 30, so we can get five equal groups but from 30, I've got 31, 32, 33, I've got three groups of 10 that I can't share equally. So I can have my five equal groups. What must I do, with my three groups of 10 that I can't share equally? Explain to your screen. Brilliant I'm going to regroup them to my ones column. So now, I've regrouped my three tens into 30 ones so now, how many ones have you got in total in your ones column now? Whisper to your screen. Fabulous I've got 36 ones. How many six is going to 36? What do you think? Shout out your answer. We've got six, we know that six times six is 36 there are six groups of six in 36. So our quotient is, how do I read that number? Zero, four, five, six, how would you read that? 456 because the zero in the thousands column is not holding our place value. So 2,736 divided by six, our quotient is equal to 456. Give yourselves a thumbs up, well done. Next, let's take a look we're going to be dividing non multiples, so we've got two new star words my turn, multiple. Your turn. Multiple is a number that is an equally divisible by another number. Next word is my turn, remainder. Your turn. A remainder is a value that cannot be divided equally. So our equation, and we're going to do this one together is 893 divided by four. What's my dividend here? Call out your answer. Great, my dividend is 893 and the divisor is four. The divisor is the number that we are dividing by. So how many equal groups are we going to split 893 into? Fabulous, groups of four, we're dividing by four our divisor is four. So, I've got, which column do I start with? Brilliant, my hundreds column because it's of the greatest value. So here, we've got eight hundreds I want to divide eight hundreds into groups of four, how many groups of four in 800? Call out your answer. Brilliant there are two groups of four in eight hundreds. Next, so that went equally we do not got to regroup that. Next, how many groups of four in nine tens? How many groups of four in nine tens? Think about using your known multiplication facts. Great, so we know that four times two is equal to eight, so we can get two groups of four 10, four and nine tens. But how much of the remainder have we got then? Call out your answer. Brilliant we've got one 10 remaining so we need to regroup our one 10 into, what am I going to regroup into? Shout out your answer. Amazing, into 10 ones. So now, how many ones do I have in my ones column? 13 ones. How many fours go into 13 ones? Think about your multiplication facts. You might have said, that four times three is equal to 12, so we can get three groups. Do I need to regroup? Yes, we've got one, one remaining. Now this is what we can do in division and you'll learn lots about this in the future. So, you can have a remainder of one. Group one did not share equally between four, so I know, if I've got a remainder of one I've got a remaining number, I know that 893 is not a multiple of four because it does not equally divide by four. And my quotient is to 223 remainder one. I've got some questions for you here now, you've got to explain your thinking out loud to your screen. It says, is Xavier correct? Solve and explain your thinking out loud. Xavier says, I know multiples of six are multiples of three. I think 438 is a multiple of three. Pause the video and decide you might need to do some workings out here, if Xavier is correct. You might have found that 48 can be partitioned into 300, 438 sorry can be partitioned into 300, 120 and 18. I know that 300 divided by three is equal to a hundred, 120 divided by three is equal to 40 and 18 divided by three is equal to six. So I know now that I've partitioned my numbers to help me that 438 is divisible by three. So we know that Xavier is correct. If you managed to prove him correct in a different way, that's absolutely fine well done. Next let's meet Yasmin. Is Yasmin correct? Solve and explain your thinking out loud. Yasmin says, I know that multiples of four are even. 438 is even. It is a multiple of four. Pause the video and explain your thinking out loud to your screen. You might need to do some workings out too. Welcome back. So I know that 400 is a multiple of four because a 100 times four is equal to 400. I've partitioned into 438, 38 is not a multiple of four. Therefore, 438 is not a multiple of four. If you found out the same way well done, or a different way well done. There are lots of different ways to solve this, but I've proven that Yasmin is incorrect. Well done if you did too. Let's take a look at your independent task. It says, which numbers are multiple of exactly three of the numbers below? Can you find a number which is a multiple of at least five of the numbers? What is the same? What is different? And what else do you notice? That sounds like a lot of questions there I'm going to show you how to do one example. So here it says, which numbers are multiples of 972 so I've got my number cards along the bottom I'm going to choose. So I said, 972 is not a multiple of five because all multiples of five end in five or zero. So I've decided it's not a multiple of five. Next, I said I think 972 is a multiple of four because it is an even number. So I'm doing my predicting now. So I don't think it's five and I do think it's four, a multiple of four. Next I said, I think 972 is a multiple of nine because 900 and 72 are both multiples of nine. So I'm predicting that it is a multiple of nine. But I'm going to check, and I'm going to check my predictions using known multiplication facts or the short division method. So have a go now, pause the video and complete your independent task, making predictions and then checking with known multiplication facts or the short division methods. Here are the answers for your independent task, well done for all your hard work, go through and check whether you found the right multiples of the number. And if you'd like to, please ask your parents or carers to share your work on Twitter, tagging @OakNational and #LearnwithOak. Now the time has come to complete your end of lesson quiz. Well done for all your hard work. See you next time.

Short division (Part 3)

Short division (Part 3)

Slide deck

Lesson details

Key learning points

Licence

Video

Worksheet

Starter quiz

4 Questions

Exit quiz

4 Questions

Lesson appears in

UnitMaths / Multiplication and division

Maths