>> 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.
We're going to learn how
to round whole numbers
in this video.
You already have
to have an understanding
of place value.
So I've shown the first few
place value right here the
ones, tens, hundreds,
remember they come
in groupings of three;
thousands, ten thousands,
hundred thousands,
etc as you go to the left.
So let's try this problem.
Round 15,637
to the nearest thousand.
Well what this is saying is
like well if we know
where 15,000 is,
right this is going
to be bigger than that, right,
15,637, and then the next
thousand that would be 16,000.
And when we say we're rounding
we're trying to figure
out which it's closer to.
So hopefully you'll you
realize that if this was
on a number line it would be
closest to 16,000.
In fact that will be the
answer to this problem.
Now sometimes it's directly
in the middle if it's directly
in the middle we always round
up we go to the next value up.
Okay. So let's --
how could we do this,
what's the method
for doing this.
Well I'm going
to right this number 15,637.
Okay. So here's what you do.
So if you're going
to the nearest thousand what I
do is I underline
up to the thousand's place,
okay and nothing after it.
The question is if I'm going
to keep that 15,000
or I'm going to go
up to 16,000.
And what we do is we look
at the number,
the digit to the right
of the thousand's place.
So I decide that if it's 5
or higher I add 1
to this number
that I've underlined okay.
So if the digit
to the right is 5
or higher I round
up so this becomes 16
and the digit you circle here,
in other words to the right
of the place value you are
rounding to that and the rest
of the digits become zeros
so we get 16,000.
So let's try that again.
So let's take this same number
and let's round it
to the nearest hundred.
Okay. So if I write this
number down, 15,637, okay.
So here's the hundreds place
the 6 so I underline
up into the hundred's place.
The other digits are going
to end up being zero
in your answer basically
but I look at this digit
to decide whether I keep this
156 or add 1 to it.
Okay. So since it's a 3,
less than 5,
I keep it the same.
So this rounds to 15,600.
Now it sounds funny we're
rounding to the nearest
hundred but what the real
question is how many hundred's
is that close to?
It's close to --
sounds funny --
but 156 hundreds, okay,
that's really how would you
see that number although we
actually read it as 15,600.
So the circled number,
right the circled number,
if it's a zero, 1, 2, 3, 4,
we keep --
keep it the same okay.
If it's a 5, 6, 7, 8 or 9,
we add 1, to that place value,
whatever it happens to be.
All right let's try this one.
Round 289,652
to the nearest thousand.
Okay. So I'm going
to write, 289,652.
And I'm going
to the nearest thousand
so this is the number,
the question is am I going
to keep that at 289 or add 1
which will be at 290
and it depends on the digit
to the right.
So since that is 5
or bigger we round up.
Remember these stay zeros
or those become zeros
and rounding
up means you add 1
so be careful
that you don't put a zero
and write 280 you're actually
adding 1 to 289
so that's 290,000.
Now this looks
like you rounded it
to the nearest 10,000 doesn't
it you can't really tell
which I rounded it to,
but if you rounded it
to the nearest 10,000 you
would also get 290,000.
All right here's another one.
Round 4,682
to the nearest ten.
Okay. I'm just going
to underline right here
at the ten --
the ten's place is the 8,
right.
So the question is am I going
to keep it 468 or is it going
to go to 469 and it depends
on that digit right there,
okay.
That digit that you circle
and anything
after would be a zero;
since it's a 2 I keep it the
same so we have 468.
That's sort
of like saying you only have a
bunch of 10 dollar bills
and you owe somebody 4,682
and you're just going
to get close.
I'm going only going
to give them 468 ten
dollar bills.
You could think
of about it that way.
All right.
Try this one on your own,
round 5,292
to the nearest hundred.
All right.
We have to find the hundred's
place, it's this 2 right here,
right.
So the numbers
after that will be replaced
with zeros, right,
those will be zeros.
And the question is do I keep
it 52 or do I add 1.
Since this next digit is a 9 I
add 1 so I get 53.
So I've rounded
to the nearest hundred.
All right.
Try this one.
Round 82,561,428
to the nearest million.
Okay. So the millions place is
this 2 right here
so I underline those.
The question is, is that going
to stay 82 or is it going
to round up to 83.
You look at the next digit,
remember if it's a 5
or more it rounds up.
So this will become 83
and then all the rest
of these six digits
become zeros.
I'm having trouble
with my pen today.
Okay. Well that's a good one
to end on so hopefully now you
understand how
to round whole numbers.
[ Pause ]
>> Please visit my website
at yourmathgal.com
where you can view all
of my videos
which are organized by topic.