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## 3rd grade

### Course: 3rd grade > Unit 3

Lesson 1: Rounding to nearest 10 or 100# Rounding to nearest 10 and 100

CCSS.Math:

Learn to round up to 4-digit numbers to the nearest ten and hundred. Created by Sal Khan.

## Want to join the conversation?

- what if its all 5(43 votes)
- If it's all five then just round to the bigger ten , hundred or thousand. like if it's five then rounded to the nearest ten would be 10 .if it's 55 rounded to the nearest hundred is 100. if the number is 555 rounded to the nearest thousand is one thousand. remember if it's five or more round it to the bigger ten, hundred or thousand. if it's 4 or smaller then round it to the smaller ten ,hundred or thousand.(34 votes)

- Can you round decimals?(24 votes)
- What the easiest way to Round?(7 votes)
- Note that 1, 2, 3, and 4 get rounded down(toward zero) and 5, 6, 7, 8 and 9 get rounded up(toward ten).

So change 1, 2, 3, and 4 to 0 and 5, 6, 7, 8 and 9 to 10.

Let's suppose that you have 8,346.

If you round 8,346 to the nearest ten, 6 becomes 10, so 8,346 becomes 8,350.

If you round 8,346 to the nearest hundreds, 4 becomes 0, so 8,346 becomes 8,300.

If you round 8,346 to the nearest thousands, 3 becomes 0, so 8,346 becomes 8,000.(14 votes)

- What is 880 to the nearest ten(7 votes)
- If a number is already a multiple of 10, then rounding it to the nearest ten won't change the number. 880 is a multiple of 10 (88 * 10 = 880), therefore 880 rounded to the nearest 10 is 880.(10 votes)

- we've got four numbers here what I want to do is try to round each of these to the nearest 10 and to the nearest hundred so I encourage you to pause the video and try that right now so let's make two columns let's make one first for the nearest nearest ten and then make another column for the nearest 100 nearest 100 and let's start with 154 so 154 what is the multiple of 10 above 154 well it's 160 and the multiple of 10 below 154 is 150 so we're going to round up to 160 or down to 150 well when we rounding to the nearest 10 we need to look at the ones place one place to the right of the place that we're rounding so we look at this 4 in the ones place since 4 is less than 5 we round down to 150 now let's think about that same number rounding to the nearest hundred so 154 to the nearest hundred so now we need to think about if we were to round up what's the multiple of a hundred above 150 for 160 isn't a multiple of 100 the multiple of 100 above 154 is 200 what's the multiple of 100 below 154 well that's going to be 100 so if we're going to round to the nearest hundred so we look at the hundreds place we'll look one place to the right of that which is the tens place if that place is five or greater we round up if it's less than 5 we round down well this is clearly 5 or greater so we round up so this is interesting when we rounded to the nearest 10 since we had a 4 in the ones place we rounded down but when we rounded to the nearest hundreds since we had a 5 in the tens place we rounded up to 200 let's do some more of these this is fun so four thousand six hundred and seventy-four four thousand six hundred and seventy for the multiple of 10 above that is four thousand six hundred and eighty the multiple of 10 below that four thousand six hundred and seventy remember we're concerned only with the multiple of 10 so do we round up or down well we're thinking about rounding the tens place so it's see that's why it's either going to be an 8 if we round up or 7 if we round down to figure that out we look at the ones place the ones place is 5 or greater we round up if it's less than 5 we round down it's once again less than 5 so we round down to 4670 now let's round the same number to the nearest hundred four thousand six hundred and seventy four what's the multiple of 100 below this well the multiple 100 below this is four thousand six hundred the multiple of 100 above this is four thousand seven hundred if we're trying to think about rounding to the nearest hundred we want to look at the tens place the tens place is five or greater so we round up to four thousand seven hundred now let's tackle nine thousand nine hundred and ninety five and once again always try to pause these if you haven't done so already to try to do this on your own so nine thousand nine hundred and ninety five what is the multiple of 10 below this well the multiple ten below this is nine thousand nine hundred and ninety and what's the multiple of 10 above this well if you increase this by ten you actually get to ten thousand you get to ten thousand so you might say hey well isn't this a multiple of 100 and actually this is a multiple of a thousand it's also a multiple of ten thousand it's all of those but the multiple of ten right above nine thousand nine hundred ninety five is ten thousand you just have to add a little bit to this to get to ten thousand or the multiple of 10 below it is clearly nine thousand nine hundred ninety 10 more than that gets you to ten thousand so how do we round this well once again if we're rounding to the nearest ten we want to look at the ones place the ones place is five or greater so we round up to ten thousand now let's round to the nearest hundreds we should be getting used to this now to the nearest hundreds what is the hundreds below this well it's nine thousand nine hundred nine thousand nine hundred what is a hundred above this and next multiple of 100 above this well if you add 100 to 9900 you once again get 10,000 so how do we decide whether to round up or down well we don't look at the ones place anymore we're now rounding to the nearest hundred so we want to round to the nearest hundred to do that we look one place to the right which is the tens place if this is five or greater we round up if it's less than 5 we round down it is 5 or greater so once again we round up to 10,000 now we have one more eight thousand three hundred and forty six so eight thousand eight thousand three hundred and forty six the tens place or that the multiple of 10 below it is eight thousand three hundred and forty multiple of 10 above that is eight thousand three hundred and fifty if we're going to round to the nearest ten we need to look at the ones place the ones place is five or greater so we round up now let's round to the nearest hundred eight thousand three hundred and forty six the hundreds multiple of 100 above this is eight thousand four hundred the multiple of 100 below this is eight thousand three hundred notice we're rounding to the nearest hundreds if we were to round up the hundreds place becomes a four if we round down the hundreds place stays of three but it's followed by zeros if we want to round to the nearest hundreds we need to look at the tens place the tens place here is less than 5 so we round down to eight thousand three hundred notice again when we rounded to the nearest tens we rounded up to eight thousand three hundred fifty when we round to the nearest hundreds we rounded down to eight thousand three hundred

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Round to nearest 10 or 100 on the number line Round to nearest 10 or 100

Gosh i love math hehee(9 votes)- The answers are wrong(3 votes)

- can you round up or down with negetive(10 votes)
- How could I show 1900 ( year ) rounded to the nearest tens.(5 votes)
- yes that is so true 1900 rounded is 1900(4 votes)

- So everyone can round what so can animals round? please help me with this i'm so frustraded im going to expolde also i'm hungry when i'm stressed i'm hungry.(6 votes)
- Is it possible to round with a calculator.(5 votes)
- yeah, only if you get those 100 doller ones right(4 votes)

- Why does any 5 round up?(4 votes)
- Because there has to be some number to be the lowest number for rounding up and in most problems it makes more sense to round up, so it makes sense to give rounding up the extra number.(4 votes)

## Video transcript

We've got four numbers here. What I want to do is try
to round each of these to the nearest 10 and
to the nearest hundred. So I encourage you to pause the
video and try that right now. So let's make two columns. Let's make one first
for the nearest 10 and then make another
column for the nearest 100. And let's start with 154. So 154, what is the
multiple of 10 above 154? Well, it's 160. And the multiple of
10 below 154 is 150. So we're going to round
up to 160 or down to 150. Well, when we're rounding
to the nearest 10, we need to look
at the ones place. One place to the right of the
place that we're rounding. So we look at this
4 in the ones place. Since 4 is less than 5,
we round down to 150. Now, let's think about
that same number, rounding to the nearest hundred,
so 154 to the nearest hundred. So now we need to think
about if we were to round up, what's the multiple
of 100 above 154? 160 isn't the multiple of 100
The multiple of 100 above 154 is 200. What's the multiple
of 100 below 154? Well, that's going to be 100. So if we're going to round
to the nearest hundred-- so we look at the hundreds place. We'll look one
place to the right of that, which is
the tens place. If that place is 5 or
greater, we round up. If it's less than
5, we round down. Well, this is clearly 5
or greater so we round up. So this is interesting. When we rounded to the
nearest 10, since we had a 4 in the ones place,
we rounded down. But when rounded to
the nearest hundreds, since we had a 5 in the tens
place, we rounded up to 200. Let's do some more of these. This is fun. So 4,674. The multiple of 10
above that is 4,680. The multiple of 10
below that, 4,670. Remember, we're concerned
only with the multiple of 10. So do we round up or down? Well, we're thinking about
rounding the tens place. So that's why it's either going
to be an 8 if we round up, or a 7 if we round down. To figure that out, we
look at the ones place. If the ones place is 5
or greater, we round up. If it's less than
5, we round down. It's, once again, less than
5, so we round down to 4,670. Now let's round the same
number to the nearest hundred. What's the multiple
of 100 below this? Well, the multiple of
100 below this is 4,600. The multiple of 100
above this is 4,700. If we're trying to think
about rounding to the nearest hundred, we want to
look at the tens place. The tens place is 5 or greater,
so we round up to 4,700. Now let's tackle 9,995. And once again,
always try to pause these, if you haven't
done so already, to try to do this on your own. So 9,995. What is the multiple
of 10 below this. Well the multiples of
10 below this is 9,990. And what's the multiple
of 10 above this? Well, if you increase this by
10, you actually get to 10,000. So you might say, hey, well
isn't this a multiple of 100, and actually this is a
multiple of a thousand-- it's also a multiple of 10,000. It's all of those,
but the multiple of 10 right above
9,995 is 10,000. You just have to add a little
bit to this to get to 10,000. Or the multiple of 10
below it is clearly 9,990. 10 more than that
gets you to 10,000. So how do we around this? Well, once again, if we're
rounding to the nearest 10, we want to look
at the ones place. The ones place is 5 or greater
so we round up to 10,000. Now, let's round to
the nearest hundreds. You should be getting
used to this now. To the nearest hundreds, what
is the hundreds below this? Well, it's 9,900. What is 100 above this, the
next multiple of 100 above this? Well, if you add 100 to 9,900
you once again get 10,000. So how do we decide whether
to round up or down? Well, we don't look at
the ones place anymore. We're now rounding to
the nearest hundred. So we want to round to
the nearest hundred. To do that, we look
one place to the right, which is the tens place. If this is 5 or
greater, we round up. If it's less than
5, we round down. It is 5 or greater so once
again we round up to 10,000. Now we have one more, 8,346. The multiple of 10
below it is 8,340. Multiple of 10
above that is 8,350. If we're going to round
to the nearest 10, we need to look
at the ones place. The ones place is 5 or
greater, so we round up. Now, let's round to
the nearest hundred. 8,346, the multiple of
100 above this is 8,400. The multiple of 100
below this is 8,300. Notice we're rounding
to the nearest hundreds. If we were to round up, the
hundreds place becomes a 4. If we round down, the
hundreds place stays at 3, but it's followed by zeroes. If we want to round to
the nearest hundreds, we need to look
at the tens place. The tens place here is less than
5, so we round down to 8,300. Notice, again, when we
round to the nearest tens, we rounded up to 8,350. When we round to the
nearest hundreds, we rounded down to 8,300.