Video Transcript
Subtracting from 10
In this video, we will learn how to use models and subtraction sentences to find all the ways to subtract from the number 10. You could use a ten frame and some counters to help you find all the ways to subtract from 10. And you could start by subtracting one. 10 subtract one equals nine. It’s important to write down our subtraction sentences or subtraction equations as we go. This will help us remember which subtraction sentences we’ve already found. 10 take away two is eight.
We could also use cubes or cube train to find all the ways to subtract from 10. Remember, we need to record or write down all our subtraction equations so we can remember what we’ve taken away from 10 already. 10 take away seven equals three. Could we make another subtraction sentence using these three numbers? Is there another way that we could take away from 10? Yes, there is. 10 subtract seven equals three, and 10 subtract three equals seven. We just swapped these two numbers around. Let’s look closely at our subtraction equations. What do you notice? 10 subtract one equals nine. 10 subtract two equals eight. 10 subtract three equals seven. 10 subtract four equals six. 10 subtract five equals five. 10 subtract six equals four. 10 subtract seven equals three.
What do you think the next subtraction equation would be? Well, we know it’s going to start with a 10 because that’s the number we’re subtracting from. How many should we subtract? Eight. Did you notice that the number we’re subtracting each time increases by one? One, two, three, four, five, six, seven, eight. What is 10 subtract eight? Can we use the subtraction sentences that we’ve already written to help us find the answer? Yes, we can. The number of cubes that are left decreases by one each time. Nine, eight, seven, six, five, four, three, two. 10 take away eight equals two. We haven’t found all the ways to take away from 10. Let’s have a go at some questions now, where we can use part–whole models, cube trains, or ten frames to help us find ways to take away from 10.
The following model shows a way to subtract from 10. 10 take away four equals six. Here is a subtraction model for 10 take away what equals two. What’s the missing number? Is it 12, two, or eight? Find the model that represents 10 take away three.
This question has two parts. In the first part of the question, we have to find the missing number in this subtraction sentence. And we’re given a part–whole model to help. And we’re also given a choice of three numbers that we can use to complete the sentence and the part–whole model. Is it 10 subtract 12 equals two, 10 subtract two equals two, or 10 subtract eight equals two? Do you know the answer? Let’s use a ten frame and 10 counters to help us find the missing number. What number do we subtract from 10 to leave us with two?
Let’s subtract some counters. One, two, three, four, five. Remember, we need to be left with just two counters. Let’s keep subtracting. Now we’ve taken away six, seven, eight. And we’ve got two counters left. So 10 take away eight equals two. The missing number is number eight. 10 subtract eight equals two.
Now we can answer the second part of our question. We’re shown three different part–whole models. And we have to find the one which represents or shows 10 take away three. Each of the part–whole models has 10 as the whole amount. That’s because we’re subtracting from 10. Let’s look at the first part in each of our part–whole models. In the first model, one of the parts is a five. In the second model, one of the parts is a seven. And in the third model, one of the parts is a one.
We’re looking for the part–whole model where one of the parts is a three because our subtraction sentence is 10 take away three. Which of our part–whole models has three as one of its parts? It’s this one. 10 take away three equals seven. This is the part–whole model which represents 10 take away three equals seven.
Liam is subtracting from 10. Write the missing equation. 10 subtract five equals five. 10 take away six equals four. 10 subtract seven equals three. And we have the missing equation. And 10 take away nine equals one. Is the missing equation 10 subtract six equals four, 10 subtract eight equals two, 10 subtract seven equals three, or 10 subtract eight equals three?
This question is all about subtracting from 10. And we can see from the model that the cube trains all contain 10 cubes. We’re also given the subtraction equations or the subtraction sentences that go with each model. 10 take away five is five, 10 take away six is four, 10 take away seven is three, this subtraction equation is missing, and then we have 10 take away nine equals one. How can we work out the missing subtraction sentence? Well, we could look at the model and we could count the number of cubes that have been crossed out or taken away.
But a quicker way would be to use our subtraction equations. We know the equation starts with the number 10 because we’re subtracting from 10 in this question. Let’s look at the number that we’re taking away each time. 10 take away five, then six, then seven, then eight, then nine. Did you notice that the amount we’re subtracting each time is increasing by one? We’re taking away one more each time. Now we can cross out some of our possible answers. It can’t be 10 take away six or 10 take away seven. We’re taking away eight. Now what we need to do is work out what’s left if we take away eight from 10.
Let’s look at the amount of cubes that are left after we’ve taken some away. Five, four, three, two, one. The number of cubes we have left decreases by one. That’s because we’re taking away one more each time. So the amount we have left goes down by one each time. The missing equation is 10 subtract eight equals two. 10 take away five is five, 10 take away six is four, 10 take away seven is three, and 10 take away eight is two. The missing subtraction equation is 10 take away eight equals two.
Michael is subtracting from 10. Write the missing equation. 10 take away one equals nine. 10 take away two equals eight. 10 take away three equals seven. Then we have the missing equation. 10 take away five equals five. And 10 take away six equals four. Is the missing equation 10 subtract four equals seven, 10 take away three equals seven, 10 take away five equals six, or 10 take away four equals six?
This question is all about subtracting from 10. Looks like Michael is trying to find all the ways to take away from 10 using a ten frame and some counters. And he’s writing a subtraction equation for each of his models. 10 take away one equals nine. 10 take away two equals eight. 10 take away three equals seven. But the subtraction sentence for this model is missing. What should the equation be? Well, we know he’s subtracting from 10 because the question tells us and also each of the ten frames has 10 counters.
How many counters has Michael crossed out in his ten frame? How many is he taking away from 10? He’s taking away four. How many counters are left? 10 take away four equals six. Michael had 10 counters. He took four away. There are six left. The missing equation is 10 take away four equals six.
What have we learned in this video? We’ve learned how to use models and subtraction equations to find all the ways to subtract from 10. Did you find all the ways to subtract from 10? 10 take away zero equals 10. 10 take away one is nine. 10 take away two is eight. 10 subtract three equals seven. 10 subtract four is six. 10 take away five equals five. 10 take away six equals four. 10 take away seven is three. 10 subtract eight equals two. 10 subtract nine equals one. And 10 subtract 10 equals zero.
