### Video Transcript

Which of these has a different
answer? Three plus three. One plus five. Three plus four. Or two plus four.

We can see that these four
different additions are also shown as a model using both blue and orange
rectangles. Can you see what the first
number in each addition represents? It’s the number of blue
rectangles, isn’t it? For example, in the first
addition sentence or equation, we have three blue rectangles. That’s why our first number is
three. And we also have three orange
rectangles. That’s why the second number in
our equation is three. So what is three plus
three? Let’s start by saying the first
number and then counting on another three. So we’ll say three, four, five,
six. There are six rectangles in our
first model. Three plus three equals
six.

In our second model, we can see
that we have one blue rectangle and five orange rectangles, so we can start with
the number one and count on another five. One, two, three, four, five,
six. Our second number sentence also
shows six. And if we compare the length of
our models, we can see they’re both the same length. They both contain six
rectangles, don’t they?

What about our next number
sentence, three plus four. We’ll start with three and
count on four. Three, four, five, six,
seven. This number sentence has an
answer of seven. And if we look at the length of
the model, we can see that this is longer than the rest. The number sentence with a
different answer is three plus four. We know this because if we
start on two and count on another four, we’re going to arrive at six. Two, three, four, five,
six. The addition that has a
different answer is the one that shows three plus four.