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G'day students, I'm Dr Price. In this video I'm going to talk to you about some Addition
Facts called "Count on 2 Facts". And were going to use two different ways to help us
to learn these number facts, a "Number Line" and a "Ten Frame", so let's start with a number
line, and let's look at the question, "4 +2 =?" This is a nice easy number fact and using
the number line I'm sure you won't find it difficult. We're going to start with 4 and
then count on 2, look at the number line, find the number 4 imagine the two jumps; you
can draw the two jumps if you want to. "What number do we get to?" Of course it's "6".
Now with the number line it's quite easy to do, and with drawing the lines and so on you
can find the answer, but what we really want to be able to do is to imagine the jumps,
imagine the counting on two and be able to come up with the answer without using the
number line. So as you get better at this, you use the number line to start with, but
after a while you will become familiar with numbers, and you should be able to do it without
actually drawing the lines and even without the number line. The other part of this is
the "Counting on part", so you can do it without a line and just think in your mind, so again
were starting with the "4", if you think to yourself, starting from 4 "What's the next
counting number?" Of course it's "5" and "What the one after that?" That's our answer "6".
And if you do it that way, if you say the 4 and then you whisper the 5 and then say
the next number that will help you remember the jumping over two numbers. So might say
4, 5 (whispers), 6 and that gives you the answer, you can do that with any number that
we're counting on two. Here is the ten frame, I expect that you've used a ten frame before
you should be able to look at this and tell me that there are six counters. So this question
would be 6 and where going to add 2 again, because were counting on two. "How many would
we have if we add another 2?" I've put the other two out, you can see straightaway how
many, there must be "8". Could you do that without the counters, could you look at the
6 and imagine the next two, see it in your mind if you like and look at that and see
the next one is "8". Alright, so those are some easy questions, let's try some slightly
harder ones. This is a question where we don't know one of the numbers and I'm going to do
two different questions here like this, "What shall I have for this one?" Let me have "9".
Okay, so looking at the number line, here is a question were we start with a number
and we don't know what that number is yet, and we add 2, and the answer is "7". Using
the number line, here is the 7, if we started it over here we made two hops and we finish
at the 7, "Where did we start from?" So you need to look at this and work out, "Where
did we start if its two hops?" Here are two hops, one, two, so we must have started here
at the "5". So it's a little bit more difficult, you have to be able to think where have we
started, it's a bit thinking backwards from the number that we get to. And the last one,
let's put nine counters for this one, here are nine counters, "What did we start with,
if start with a number and we added 2 and the answer is 9?" So imagine the number that
was there before we put two more. Let me change the color of the last two to a different color,
can you see the number that was there before the 2? I'm sure you can. Its "7", 7 and 2
makes 9. Alright so that's the "Count on 2 Strategy" and I will talk to you next time.