In this video, we’re going to look at how to count on a number line to help us to add numbers together.
First, let’s add six and three.
Look at this addition sentence. Remember that this is the addition symbol; it tells us to add two numbers. So we have to add six and three. And remember that this symbol means equal; the number in the green box will be equal to six add three.
Now, let’s use the number line to find our sum. First, we start with six. So, let’s find six on the number line and put a counter on it. Now that the counter is on six, we have to add three; let’s jump three times. We can imagine a frog picking up the counter and helping us to make our three jumps: one, two, three.
So from six, we took one, two, three jumps. So we started on six, we took three jumps, and we landed on nine. So the sum of six and three is nine. Now our addition sentence says six add three is equal to nine. And now you know how to add using a number line. Let’s try one more question.
What is seven plus four?
Remember that plus is another word for add. So, we’ve got to add seven and four; let’s write these numbers in our addition sentence. Seven plus four equals what? We’ve got to find the total. To add seven and four, first we have to find seven on the number line. And we put our counter on the number seven. Now we have to add four.
That means we have to make four jumps on the number line, and this time that frog isn’t going to help us: one, two, three, four. So we started at seven, we added four, and we ended up at eleven. This means that eleven is equal to seven plus four.
Okay, let’s just go through the steps that we need when using a number line to add. First, find one of the numbers on the number line. Second, jump the other number of steps to count on: one, two, three, four, five. And thirdly, the number that you land on is the sum. And in this case, that was eleven. All you have to do now is find a friendly frog to help you jump along a number line to add your numbers together. Good luck.