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>> Hi, this is Julie Harland,
and I'm your Math Gal.
Please visit my website
at yourmathgal.com
where you can search for any
of my videos organized
by topic.
Most people learn
to add starting
from the right most column.
For instance,
let's take this number 537
plus 198.
So, the usual way they teach
this in school you start
over here on the right,
which is in the 1s column,
7 plus 8 is 5
but then you have
to write the 5
and carry the 1.
This is where a lot
of people get confused
and put the 1
and carry the 5 getting it
backwards,
but anyway most people learn
how to do it
without too much problem
and so we have 1,
3 and 9 that would be 13
and carry the 1
and that gives you 7.
So there's no problem
with that, but I'm going
to show you a way
to add these numbers going
from left to right
where you don't have
to do the carrying.
So, here's how it works.
I'm going to write the
different face values
in different colors.
So I'm going to put the 5s
in green and the 10s, sorry,
the 100s in green.
I'm going to put the 10s
places, which is the 3
and the 9, in purple,
and I'm going
to put the 1s here
to illustrate how I'm doing it
so you can see how I'm adding
from left to right.
So I'm starting out adding
from left to right.
I just go 5 plus 1,
which is 6.
I write the 6 down no problem.
Now, the next column is 3
plus 9.
Now watch what I'm going
to do I'm going to go down
and I'm going
to write 3 plus 9 is 12.
I'm just going
to write it here.
Then I'm going to go to the 7,
8, 7 plus 8, and that is 15
and I'm going to write 15.
I'm kind of lining
up my numbers although the 1
and the 2 don't look perfectly
lined up and then I'm going
to do it again.
So, now, I just add the 6
and 1 is 7, the 1 and 2 add
up to 3, and the 5.
Notice I get the same answer.
So, what you do is you add
and if there's no room
to write the number I just go
below and write it and then
if I have room, I can write it
up here again.
So, let's do another problem.
So, here's another problem.
Let's add from left to right.
I put it in different colors
this time so hopefully you can
follow along; 8 and 9 is 17.
So I just write 17.
Five and 8 is 13
so I need 2 places
so I'm just going
to go below here
to write the 13.
Are you with me there?
Then 6 and 2 is 8.
It doesn't matter
where you put it,
you could put it here
or you could put it next
to the 3.
The idea is
that you're just writing the
number down
and now we're going
to do it again.
If there's 2 rows like this,
you just add one more time.
So that's 1, 8, 3,
8 and there you go.
Are you ready to try one?
How about 537 plus 648.
Try that one on your own
by putting the video on pause
and trying it on your own.
All right so this time 5
and 6 is 11 so we write 11;
3 and 4 is 7, I don't need
to go below here do you
see that?
Because there's room
to put it right here;
I can put the 7 right there.
Then the 7
and 8 is 15 I could just write
the 15 right here.
Now some people actually write
the 1 here and the 5 up here.
It really doesn't matter;
what matters is you've got it
in the right column.
You want to write 1, 5.
So we have
to add one more time
since we have 2 rows.
So we have 1, 1, 8, 5.
I got it from left to right.
Now, what I
like about this method is
first of all we usually read
left to right
so that seems natural,
we don't have this problem
with the carrying thing
where you write
down the 1s number
and then have to put the 10s
up at the next place.
So, you get to stay
at your eye level
when you're writing,
you go left to right,
you don't have to worry
about adding 3 numbers
at a time because you just do
your carrying.
This is kind of like you
and you're carrying at the end
of the problem.
Let's try this one
so we're going
from left to right.
So, I have the 7
in the 1000s place
so write the 7
and then we've got 9 and 8
so let's write 17 right here
and we have 8 and 9,
I'm sorry, 8 and 1,
which is 9, and then 6
and 5 is 11.
Now we have to add again.
So, 7 and 1 is 8, 7 goes here.
Check this out we have 9
and 1 is 10 so I have
to write 10 which means I have
to add one more time 8,
8, 0, 1.
I realize this takes a little
bit more time;
it's just an alternative way
of doing addition.
You certainly don't have
to do it.
If you're comfortable
with carrying
and always get the problem
right with carrying,
it does take less space
on your paper.
So it's a perfectly good way
to do it, but I
like this method especially
for people who have trouble
with the carrying and only
like to add 2 numbers
at a time.
So let's do another one.
All right so try this one
we're going to go
from left to right.
Put the video on pause, try it
and then see how you do.
Here we go 5 and 8 is 13;
6 and 6 is 12, I'm just going
to write it like this 12;
9 and 9 is 18 so I'm going
to go here since I have room;
and 3 and 7 is 10 I'm going
to write it down here.
I'm going to add again one
more time 1, 4, 3, 9, 0.
Okay. This also works
if you're adding more
than 2 numbers together.
So let's try one of those now.
So, now we have 3 numbers
to add and we'll still go left
to right.
I'm going to do each column
in a different color.
So the 5, 8 and 4
so you can see what happens
again, what is that?
So, unfortunately,
I have to add these 3 numbers
so that's 13 plus 4 is 17
so I'm going to write 17.
The next column I have 3,
6 and 2 that's 11 so I'm going
to write 11 right here;
and the next column I'll do
in purple 2, 5 and 8 that's 7
and 8 is 15 so 'm going
to put the 15 like this
and then we add up 1, 8, 2, 5.
It really doesn't take much
more time than doing it the
way with carrying,
but just an alternative.
So here's one for you
to try 3 numbers.
Okay so try this problem.
Put the video on pause and try
that on your own.
Let's do it starting going
from left to right.
Nine and 5 and 7 that's 21; 8,
3 and 7 that's 18
so I'm just going
to write the 18 here; 6,
8 and 6 that adds up to 20;
and so we have to do it again,
add, 2, 2, oh, I 2 [inaudible]
so I'll have
to write the 10 one more time
this is still 0, so we get 2,
3, 0, 0, 2,300.
Let's add 4 numbers.
All right so here are 4
numbers to add.
I'm just going to go left
to right again.
So, let's see 5, 6, 10,
12 that's 5, 1 and 4
and 2 adds up to 12.
Next column I've got 6 and 6
and 2 so that's 12, 13,
14 so I'm going to go
down here to fit in that 14;
2, 5, 2 and 3 what's that 9,
10, 11, 12.
So I'm going to put that here,
12; 4, 3, 5 and 6 that's 18;
so we put the 18 here.
Then we just add one more
time, 1, 3, 5, 3,
8 and there it is, all right.
So hopefully you learned
something new
and if you know anybody having
trouble with addition
with carrying,
you might show them this
method or if you know any
teachers, know any kids
or just somebody who wants
to have fun with math.
Please visit my website
at yourmathgal.com
where you can view all
of my videos
which are organized by topic.