Video Transcript
Addition Equations
In this video, we’ll learn how to
read, write, and model addition equations with numbers up to 10. Here are two groups of carrots. In the first group, we can see one,
two, three, four carrots. And in the second group, we can
count one, two carrots. We know that the total number of
carrots is the same as four plus two more. This is equal to one, two, three,
four, five, six. Four carrots and two carrots is six
carrots. We’ve added four and two together
to get the answer six. But did you know, four and two
always makes six? We could show this by drawing
butterflies. Four pink butterflies and two blue
butterflies is a total of six butterflies. It doesn’t matter if we add four
marbles and two marbles or four cubes and two cubes. When we add together four and two,
it always makes six.
Now wouldn’t it be good if there
was a way to write that four and two makes six without having to draw carrots or
butterflies or marbles? Well, we can do this by writing
what’s called an equation. And because we’re showing an
addition fact, this is going to be an addition equation. Now the word equation might sound
like a tricky word, but, really, all it means is a way of showing a number fact
using numbers and symbols. In other words, we’re going to show
that four and two makes six without drawing any pictures, without writing any words,
just using numbers and symbols.
The first thing we can do is to
show the number four. And we’ve done this already at the
top, haven’t we? We can write the digit four. Here we go. Now, we need a symbol to show that
we’re going to add two. We can use the addition symbol,
which is made up of two lines across each other like this. And this symbol means add or
plus. Of course, we know we’re adding
two. So, we can read our equation so
far, four plus two.
Now, we need a symbol that
represents is equal to or makes. We want to be able to write four
plus two makes six. We can use what’s called the equals
sign. This symbol is two straight lines
like this. Four plus two is equal to, or four
plus two makes, six. So, we’ve written our number fact
as an addition equation. Four plus two equals six. Now, let’s try answering some
questions where we have to think about addition equations.
Select the right model the
represents the equation one plus three is four.
In this question, we’re given
an equation. This is a number fact that’s
made up of numbers and symbols. And in it, we can see the
addition symbol. When this appears between two
numbers, we know we need to add them together. It means plus or add. And our number fact tells us
that one add three is four. And we know this is true, don’t
we? If we have one and another
three, we’ve got four altogether. The question asks us to select
or to choose the right model that represents the equation one plus three is
four. And we’re given four possible
answers. If we look at our models, we
can see that we’re using apples to model the equation. We’ve got green apples and red
apples being added together each time.
Now which of these models
represents the equation one plus three is four? What could we look for in our
model that would show us that this was correct? We know we’re looking for a
model where the total number of apples is four. Which models show a total of
four? The total in our first model is
one, two, three, or it is four. So, our first model could be
the correct answer. Our second model shows a total
of one, two, three apples. So, this can’t be correct. Our next model shows a total of
one, two, three, four apples again. Perhaps this is the right
model. And if we look quickly at our
final model, we can see that the total is going to be more than four. It’s more than the one above,
isn’t it?
And so, there are only two
models that show a total of four apples. But which one shows one plus
three making four? Our first model shows one, two
green apples plus one, two red apples is four apples. And our next possible answer
shows one green apple plus one, two, three red apples. This is the correct answer, one
plus three. The model that represents the
equation one plus three is four is the one that shows one green apple plus three
red apples is four apples altogether.
Find the matching number
sentence for the following.
We can see what’s called a
picture equation here. It’s made up of pictures and
symbols. The first picture contains
three caterpillars. Then, we have this symbol that
looks like a cross shape. This is an addition symbol. It means plus or add. We need to add something to our
three caterpillars. Our next picture shows one
caterpillar on its own. We need to add one to our three
caterpillars. Our last picture is going to
show the total, what we get when we add our two lots of caterpillars
together. But before the last picture, we
can see one more symbol made of two lines. We call this the equals
sign. This is going to be a way of
showing what three add one makes, or what it equals. And what does it equal? Let’s count these
caterpillars. One, two, three, four, of
course. We know that three plus one
makes four, don’t we?
Now that we’ve read our picture
equation correctly, we can do what the question asks us, which is to find a
matching number sentence. Firstly, we said there were
three caterpillars in the first picture, so we’re going to write the number
three to begin with. We also said that there was one
caterpillar in the second picture. And we need to add these two
together, so we’re going to use our addition symbol. Three add one. Now, just before we write the
total, we need to use the equals sign. Three add one makes... What does it make? Three plus one equals four. Now, look at our number
sentence. There are no pictures in
it. There are no words in it. But it still tells us three
plus one equals four.
Natalie has two red cars and
Jacob has three blue cars. How many cars are there? Find the matching number
sentence. One plus one equals two. One plus two equals three. Three plus three equals
six. Three plus four equals
seven. Or two plus three equals
five.
In this question, we can see
that Natalie and Jacob have got some toy cars. We’re told that Natalie has two
red cars and Jacob has three blue cars. And the first part of our
problem asked us, how many cars are there? What’s the total number of
cars? Let’s count them. One, two, three, four. There are five cars
altogether. Two red cars and three blue
cars make five cars.
The next part of our problem
asks us to find the matching number sentence. We’re looking for a number
sentence that tells us that two red cars and three blue cars make five cars
altogether. Each of our number sentences is
an addition number sentence. We know this because they each
contain one of these symbols. This is the plus symbol. It shows us that we need to add
two numbers together.
So, we’re looking for a number
sentence that shows two plus three. Can you spot it? This number sentence shows two
plus three. But is the answer correct? Well, we can also see an equals
sign in our number sentence. This shows what two plus three
makes or is the same as. And our number sentence or
equation shows us that two plus three equals five. This is what we were looking
for.
If Natalie has two red cars and
Jacob has three blue cars, we know they have five cars altogether. And so, the matching number
sentence or equation is two plus three equals five.
So, what’ve we learned in this
video? Well, firstly, we’ve learned that
an equation or a number sentence is a way of showing a number fact using numbers and
also symbols. And so, we’ve learned how to read,
write, and model addition equations with numbers up to 10.