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Welcome to the presentation
on basic addition.
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I know what you're thinking,
Sal, addition doesn't
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seem so basic to me.
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Well, I apologize.
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Hopefully by the end of this
presentation or in a couple
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of weeks it will seem basic.
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So let's get started
with, I guess we could
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say, some problems.
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Well let's say I start
with an old classic.
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1 plus 1.
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And I think you already know
how to do this, but I'll kind
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of show you a way of doing this
in case you don't have this
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memorized or you haven't
already mastered this.
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You say, well, if I have 1,
let's call that an avocado.
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If I have 1 avocado and
then you were to give me
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another avocado, how many
avocados do I now have?
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Well, let's see.
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I have 1, 2 avocados.
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So 1 plus 1 is equal to 2.
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Now, I know what
you're thinking.
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That was too easy, so let
me give you something a
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little bit more difficult.
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I like the avocados.
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I might stick with that theme.
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What is 3 plus 4?
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This is, I think, a more
difficult problem.
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Well, let's stick
with the avocados.
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And in case you don't know what
an avocado is, it's actually
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a very delicious fruit.
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It's actually the fattiest
of all the fruits.
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You probably didn't even
think it was a fruit,
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even if you ate one.
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Let's say I have 3
avocados-- 1, 2, 3.
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And let's say you were to
give me 4 more avocados.
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So let me put this 4 in yellow
so you know that these are
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the ones you're giving me.
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1, 2, 3, 4.
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So how many total
avocados do I have now?
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That's 1, 2, 3, 4,
5, 6, 7 avocados.
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So 3 plus 4 is equal to 7.
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And now I'm going to introduce
you to another way of
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thinking about this.
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It's called the number line.
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And actually, I think this is
how I do it in my head when I
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forget-- if I don't
have it memorized.
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So number line, I just write
all the numbers in order.
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And I go high enough just
so all the numbers I'm
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using are kind of in it.
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So you know the first number
is 0, which is nothing.
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Maybe you don't know,
but now you know.
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And then you go to 1, 2,
3, 4, 5, 6, 7, 8, 9, 10.
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Keeps going-- 11.
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So we're saying 3 plus 4.
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So let's start at 3.
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So I have 3 here and we're
going to add 4 to that 3.
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So all we do is we go up the
number line, or we go to the
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right on the number
line, 4 more.
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So we go 1, 2, 3, 4.
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Notice all we did is we just
increased it by one, by
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two, by three, by four.
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And then we ended up at 7.
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And that was our answer.
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We can do a couple
of different ones.
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What if I asked you
what 8 plus 1 is?
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Well, you might
already know it.
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You know, plus 1 is
just the next number.
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But if we look at the
number line you start
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at 8 and you add 1.
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8 plus 1 is equal to 9.
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Let's do some harder problems.
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And just so you know, if you're
a little daunted by this
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initially, you can always
draw the circles.
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You can always do
the number line.
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And eventually, over time, the
more practice you do-- you'll
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hopefully memorize these and
you'll do these problems
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in like half a second.
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I promise you.
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You just got to
keep practicing.
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I want to draw the number line
again, actually, I have a line
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tool, so I should give you
all those ugly looking lines
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that I've been giving you.
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Look at that.
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That's amazing.
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Let me see.
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Look at that.
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That's a nice looking line.
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I'm going to feel bad
to erase it later on.
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So let me draw a number line.
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0, 1, 2, 3, 4, 5, 6, 7, 8,
9, 10, 11, 12, 13, 14, 15.
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So let's do a hard problem.
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I'm going to do it in
different colors now.
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5 plus 6.
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So if you want, you could
pause the video and try this.
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You might already
know the answer.
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And the reason why I say this
is a hard problem is because
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the answer has more numbers
than figures, so you can't
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necessarily do it
on your fingers.
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So let's get started
with this problem.
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Actually, my phone is ringing,
but I'm going to ignore the
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phone because you're
more important.
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OK, let's start at the 5.
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So we start at the 5 and
we're going to add 6 to it.
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So we go 1, 2, 3, 4, 5, 6.
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And we're at 11.
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So 5 plus 6 is equal to 11.
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Now I'm going to ask you a
question, what is 6 plus 5?
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Well, we're now
going to see that.
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Can you switch the two numbers
and get the same answer?
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Well, let's try that.
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And I'm going to try it in
a different color so we
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don't get all confused.
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So let's start at 6.
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Ignore the yellow for
now and add 5 to it.
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1, 2, 3, 4, 5.
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We get to the same place.
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And I think you might want
to try this on a bunch of
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problems and you'll see
it always works out.
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That it doesn't matter what
order-- 5 plus 6 is the
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same thing as 6 plus 5.
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And that makes sense.
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If I have 5 avocados
and you give me 6,
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I'm going to have 11.
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If I have 6 avocados and
you gave me 5, I'm going
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to have 11 either way.
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Since this number line is so
nice, I want to do a few
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more problems using it.
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Although as I use it I'm sure
I'll just continue to confuse
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you because I'll write
so much on top of it.
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But let's see.
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I'll use white now.
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What is 8 plus 7?
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Well, if you can still read
this, 8 is right here.
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We're going to add 7 to it.
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1, 2, 3, 4, 5, 6, 7.
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We go to 15.
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8 plus 7 is 15.
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So hopefully that gives
you a sense of how to do
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these types of problems.
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I guess this and you're going
to learn multiplication in a
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little bit, but these types of
problems are-- when you're
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getting started off in
mathematics, these kind of
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require the most practice and
to some degree, you have to
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start memorizing them.
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But over time, when you look
back, I want you to remember
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how you feel while you're
watching this video right now.
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And then I want you to watch
this video in like 3 years and
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remember how you felt when
you're watching it now.
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And you're going
to be, oh my God.
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This was so easy because you're
going to learn it so fast.
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So anyway, I think
you have an idea.
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If you don't know the answer to
any of the additional problems
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that we give in the exercises
you can press the hints and
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it'll draw circles and you can
just count up the circles.
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Or if you want to do it
on your own so you get
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the problem right, you
could draw the circles.
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Or you could draw a number
line like we did in
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this presentation.
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I think you might be ready to
tackle the addition problems.
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Have fun.