What I want to do in this video is one, just do a bunch of
addition examples so that we really get some good practice
and we really get warmed up with addition.
And what I even more want to show you is that we now have
all the tools we need to really tackle any addition problem.
So let's just get warmed up with some one-digit addition
problems, but these are the ones that always give me a
little bit of a headache.
Let's start with a really, relatively straightforward.
I want to say 2 plus 4.
Well, we know what that is.
I don't think we need to draw the number line at this
point, but you can if you need to remember this.
2 plus 4 is 6.
Not too bad.
What about 9 plus 3?
We saw that in the last video.
9 plus 1 is 10.
Plus another 1 is 11.
Plus 3 is 12.
9 plus 3 is 12.
And it's probably not a bad idea.
It's good to visualize what's happening here, but it's also
not a bad idea to be able to do these very fast.
To be able to memorize, at least what the one-digit
addition problems end up being.
Let's do a couple of harder ones.
6 plus 7.
This one I used to find difficult to remember.
But 6 plus 7 is 13.
Draw out the number lines and the lemons and limes
if you don't believe me.
6 four 7 is 13.
8 plus 6 or 6 plus 8 is going to be 14.
And that's the same thing as 7 plus 7-- is
also going to be 14.
And if you think about it, we got the same
number here as there.
And it makes sense, right?
Because we took one away from 8, but we had one more than 6.
So it's like you just shifted the 1 from the 8 to the 6.
That's why we got the same answer.
If that confused you, ignore it.
Let's just do a couple of more of these.
So 8 plus 8 is 16.
These are things that hopefully you'll be able to do super fast
in the not too far off future.
5 plus 6.
Well, that's 11.
Let me just do a couple of more really fast.
So let's say 7 plus 9 is going to be 16.
You might want to draw the number line if
you don't believe me.
And that's going to be the same thing as 8 plus 8, is also 16.
And the 9 plus 9 is 18.
And then 9 plus 8 is 17.
And that's just a little bit of warm up.
We didn't do all of the possible combinations of
one-digit numbers, but these are some of the ones that
give people a little bit more headache.
So now that we've done that let's tackle some larger digit
numbers that we started doing in the previous video.
Maybe I'll leave that there for now.
So let's do a couple of them.
Let's do 22 plus 3.
So we go to the ones place.
2 plus 3 is 5.
We didn't have to carry anything.
And then in the tens place we just have this 2 sitting here.
So we just take that 2.
2 plus nothing-- it's two 10's.
It's two dimes.
So then we put that down there.
So we get 25.
2 dimes and 5 pennies, or $0.25 depending-- a lot of people,
money makes it easier to understand things or maybe
to be motivated to understand things.
All right, let's do another one.
What is 38 plus 17?
So we look at just the ones place.
What is 8 plus 7?
We haven't done that one yet; I'll do it up here.
8 plus 7 is equal to-- it's going to be one
more than 8 plus 6.
8 plus 6 is 14, than 8 plus 7 is going to be
one more than that.
So it's going to be equal to 15.
So in this problem we write the 5 here.
Let me write this in a different color.
So the 5 in the 15 we'd write right down there
in the ones place.
And we would carry the 1 because that's one dime.
That's one 10.
You know, this 15, this is 10 plus 5.
So this 1 really means one 10 or one dime.
So we put that 1 up there in the tens place.
We have 1 plus 3 is 4.
Plus 1 is 5.
So you get 55.
1 plus 3 plus 1 is this 5.
38 plus 17 is 55.
Or five 10's and five 1's.
That's the same thing as 55.
Let's do a couple more problems.
I think you'll see that we have the tools to tackle
anything, any problem.
Let's say we have 47.
Let me switch colors just so it stays interesting.
47 plus 9.
We just look at the ones place.
7 plus 9.
We know what that is already.
We did that problem already.
7 plus 9 is 16.
So you write the 6 in the ones place and carry the one.
And now it's in the tens place.
Because this is one 10 right there.
So 1 dime plus 4 dimes is 5 dims.
So it's 5 dimes and 6 pennies.
It's 56.
Let's do slightly harder problems.
Let me scroll down a little bit so we have some
space to work with.
We always need that.
All right, let's do something hard.
99 plus 88.
That's a hard one.
And you just have to look at the parts of the problem and
you'll see how it'll all work out.
You say, what's 9 plus 8?
We did that up here.
9 plus 8 we know already is 17.
That's a good one to remember.
9 plus 8 is 17, but it's always good to be able
to visualize it as well.
so 9 plus 8 is 17.
Carry the 1.
And then we have 1 plus 9 is 10.
10 plus 8 is 18.
Now this is interesting.
We want to write 18 down.
So we write our 8 down there.
We have 1 plus 9 plus 8.
1 plus 9 plus 8 is equal to 18.
We wrote the 8 down there and we say, let's carry the 1.
We carry the 1, but we carry it into the hundreds place.
This was the ones place, the tens place, now we're
in the hundreds place.
But there's nothing else in the hundreds place.
So it just drops straight down.
So you could almost just write the 18 just like that.
So 99 plus 88 is 187.
Let's keep doing some examples.
You could see, it's all the same pattern.
We could add two ten-digit numbers to each other as
long as we're just careful about carrying our digits.
So let's do 700-- let me switch colors.
Well do some three-digit numbers.
Let's do a four-digit number.
Let's not mess around.
Let's do a four-digit number.
So let's do 4,368 plus 572.
Let's see what happens here.
I'll write it down here.
8 plus 2.
We know that that is equal to 10.
You can do the number line if you need to.
8 plus 2 is equal to 10.
Put the 0 on the ones place, carry the 1.
Now we're in the tens place.
This is really one 10.
This is six 10's.
This is seven 10's.
Or you could think of them as dimes if we're
thinking about change.
So 1 dime plus 6 dimes is 7 dimes.
7 dimes plus 7 dimes is 14.
Let me write if like this.
We could write 1 plus 6 plus 7 is equal to-- 1 plus 6 is 7.
7 plus 7 is 14.
So this right here is going to be equal to 14.
Carry the 1.
Now we have-- let me do it in another color.
I'll do it in pink.
We have 1 plus 3.
We're in the hundreds place now.
Plus 5.
1 plus 3 plus 5.
Well, 1 plus 3 is 4.
Plus 5 is 9.
4 plus 5 is 9, so this is going to be equal to 9.
Nothing to carry.
We only had something in our ones place.
9 is just 9 pennies.
It's no dimes.
It's just 9 pennies.
And then we go to the thousands place.
Nothing to add to the thousands place.
So you just take this 4,000-- you see a 4 here, but since
it's in the fourth digit to the left, this means 4,000.
So this 4,000 right here, we don't have any other thousands
to add it to, so we just bring it straight down.
So you bring the 4 down there.
So 4,368 plus 572 is 4,000-- we'll put a comma there
to make it easy to read.
4,940.