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What I want to do in this video is one, just do a bunch of

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addition examples so that we really get some good practice

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and we really get warmed up with addition.

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And what I even more want to show you is that we now have

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all the tools we need to really tackle any addition problem.

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So let's just get warmed up with some one-digit addition

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problems, but these are the ones that always give me a

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little bit of a headache.

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Let's start with a really, relatively straightforward.

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I want to say 2 plus 4.

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Well, we know what that is.

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I don't think we need to draw the number line at this

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point, but you can if you need to remember this.

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2 plus 4 is 6.

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Not too bad.

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What about 9 plus 3?

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We saw that in the last video.

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9 plus 1 is 10.

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Plus another 1 is 11.

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Plus 3 is 12.

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9 plus 3 is 12.

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And it's probably not a bad idea.

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It's good to visualize what's happening here, but it's also

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not a bad idea to be able to do these very fast.

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To be able to memorize, at least what the one-digit

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addition problems end up being.

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Let's do a couple of harder ones.

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6 plus 7.

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This one I used to find difficult to remember.

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But 6 plus 7 is 13.

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Draw out the number lines and the lemons and limes

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if you don't believe me.

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6 four 7 is 13.

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8 plus 6 or 6 plus 8 is going to be 14.

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And that's the same thing as 7 plus 7-- is

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also going to be 14.

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And if you think about it, we got the same

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number here as there.

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And it makes sense, right?

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Because we took one away from 8, but we had one more than 6.

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So it's like you just shifted the 1 from the 8 to the 6.

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That's why we got the same answer.

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If that confused you, ignore it.

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Let's just do a couple of more of these.

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So 8 plus 8 is 16.

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These are things that hopefully you'll be able to do super fast

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in the not too far off future.

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5 plus 6.

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Well, that's 11.

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Let me just do a couple of more really fast.

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So let's say 7 plus 9 is going to be 16.

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You might want to draw the number line if

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you don't believe me.

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And that's going to be the same thing as 8 plus 8, is also 16.

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And the 9 plus 9 is 18.

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And then 9 plus 8 is 17.

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And that's just a little bit of warm up.

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We didn't do all of the possible combinations of

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one-digit numbers, but these are some of the ones that

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give people a little bit more headache.

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So now that we've done that let's tackle some larger digit

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numbers that we started doing in the previous video.

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Maybe I'll leave that there for now.

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So let's do a couple of them.

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Let's do 22 plus 3.

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So we go to the ones place.

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2 plus 3 is 5.

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We didn't have to carry anything.

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And then in the tens place we just have this 2 sitting here.

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So we just take that 2.

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2 plus nothing-- it's two 10's.

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It's two dimes.

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So then we put that down there.

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So we get 25.

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2 dimes and 5 pennies, or $0.25 depending-- a lot of people,

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money makes it easier to understand things or maybe

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to be motivated to understand things.

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All right, let's do another one.

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What is 38 plus 17?

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So we look at just the ones place.

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What is 8 plus 7?

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We haven't done that one yet; I'll do it up here.

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8 plus 7 is equal to-- it's going to be one

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more than 8 plus 6.

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8 plus 6 is 14, than 8 plus 7 is going to be

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one more than that.

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So it's going to be equal to 15.

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So in this problem we write the 5 here.

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Let me write this in a different color.

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So the 5 in the 15 we'd write right down there

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in the ones place.

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And we would carry the 1 because that's one dime.

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That's one 10.

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You know, this 15, this is 10 plus 5.

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So this 1 really means one 10 or one dime.

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So we put that 1 up there in the tens place.

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We have 1 plus 3 is 4.

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Plus 1 is 5.

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So you get 55.

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1 plus 3 plus 1 is this 5.

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38 plus 17 is 55.

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Or five 10's and five 1's.

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That's the same thing as 55.

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Let's do a couple more problems.

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I think you'll see that we have the tools to tackle

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anything, any problem.

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Let's say we have 47.

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Let me switch colors just so it stays interesting.

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47 plus 9.

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We just look at the ones place.

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7 plus 9.

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We know what that is already.

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We did that problem already.

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7 plus 9 is 16.

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So you write the 6 in the ones place and carry the one.

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And now it's in the tens place.

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Because this is one 10 right there.

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So 1 dime plus 4 dimes is 5 dims.

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So it's 5 dimes and 6 pennies.

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It's 56.

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Let's do slightly harder problems.

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Let me scroll down a little bit so we have some

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space to work with.

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We always need that.

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All right, let's do something hard.

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99 plus 88.

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That's a hard one.

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And you just have to look at the parts of the problem and

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you'll see how it'll all work out.

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You say, what's 9 plus 8?

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We did that up here.

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9 plus 8 we know already is 17.

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That's a good one to remember.

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9 plus 8 is 17, but it's always good to be able

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to visualize it as well.

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so 9 plus 8 is 17.

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Carry the 1.

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And then we have 1 plus 9 is 10.

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10 plus 8 is 18.

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Now this is interesting.

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We want to write 18 down.

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So we write our 8 down there.

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We have 1 plus 9 plus 8.

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1 plus 9 plus 8 is equal to 18.

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We wrote the 8 down there and we say, let's carry the 1.

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We carry the 1, but we carry it into the hundreds place.

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This was the ones place, the tens place, now we're

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in the hundreds place.

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But there's nothing else in the hundreds place.

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So it just drops straight down.

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So you could almost just write the 18 just like that.

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So 99 plus 88 is 187.

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Let's keep doing some examples.

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You could see, it's all the same pattern.

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We could add two ten-digit numbers to each other as

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long as we're just careful about carrying our digits.

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So let's do 700-- let me switch colors.

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Well do some three-digit numbers.

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Let's do a four-digit number.

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Let's not mess around.

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Let's do a four-digit number.

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So let's do 4,368 plus 572.

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Let's see what happens here.

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I'll write it down here.

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8 plus 2.

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We know that that is equal to 10.

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You can do the number line if you need to.

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8 plus 2 is equal to 10.

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Put the 0 on the ones place, carry the 1.

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Now we're in the tens place.

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This is really one 10.

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This is six 10's.

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This is seven 10's.

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Or you could think of them as dimes if we're

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thinking about change.

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So 1 dime plus 6 dimes is 7 dimes.

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7 dimes plus 7 dimes is 14.

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Let me write if like this.

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We could write 1 plus 6 plus 7 is equal to-- 1 plus 6 is 7.

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7 plus 7 is 14.

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So this right here is going to be equal to 14.

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Carry the 1.

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Now we have-- let me do it in another color.

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I'll do it in pink.

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We have 1 plus 3.

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We're in the hundreds place now.

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Plus 5.

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1 plus 3 plus 5.

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Well, 1 plus 3 is 4.

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Plus 5 is 9.

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4 plus 5 is 9, so this is going to be equal to 9.

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Nothing to carry.

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We only had something in our ones place.

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9 is just 9 pennies.

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It's no dimes.

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It's just 9 pennies.

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And then we go to the thousands place.

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Nothing to add to the thousands place.

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So you just take this 4,000-- you see a 4 here, but since

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it's in the fourth digit to the left, this means 4,000.

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So this 4,000 right here, we don't have any other thousands

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to add it to, so we just bring it straight down.

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So you bring the 4 down there.

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So 4,368 plus 572 is 4,000-- we'll put a comma there

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to make it easy to read.

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4,940.