Video Transcript
Which number is shown by the
model? 15, 16, or 17.
In the picture, we can see a
model. In maths, when we talk about
models, we just mean a way of showing a number. And this way of showing a number
involves two ten frames and some counters. But what number does this model
show? Underneath, we’ve got three numbers
to choose from. Can you read them? 15, 16, and 17. These are all teen numbers, aren’t
they? And we get to each of these numbers
by counting to 10 and then counting some more. We know that the number 15 is five
more than 10. One, two, three, four, five, six,
seven, eight, nine, 10, 11, 12, 13, 14, 15. And if 15 is five more than 10, 16
must be six more than 10 and 17 must be seven more than 10.
Perhaps we could use what we know
about these numbers to help us answer the question. Let’s get back to our ten frame and
counters. What do you notice about them? Well, if we look at our first ten
frame to begin with, we can see there’s no space left on it. It’s a full ten frame. Do you remember how many counters a
ten frame holds? I’ll give you a clue; it’s not
called an eight frame or a nine frame, is it? We call it a 10 frame because it
holds 10. Our full ten frame shows the number
10.
But we can see some more counters
in the second ten frame. How many more than 10 are
there? We can see another one, two, three,
four, five, six, seven. So we can see 10 counters and then
seven more counters. Now which of our three numbers did
we say was the same as 10 and then seven more? It’s 17. We can check we’re right by
counting all the counters. 10 in the first ten frame and then
11, 12, 13, 14, 15, 16, 17. Our model shows 10 counters and
then seven more counters. And so we know the number shown by
the model is 17.
