Hello, my name is Grace, and welcome to Rounding 2.
In this video you'll learn to round to the nearest hundred and nearest thousand.
This video follows Rounding 1.
Be sure to check out that video before continuing with this one.
Let's quickly review the rounding rule.
If the digit to the right of the given place value is between 5 and 9, you round up.
This means the digit in a given place is increased by one,
if the digit to the right is 5 or more.
If the digit to the right of the place value is between 1 and 4, you round down.
The number in the given place value remains the same
if the digit to the right is less than 5.
Now, let's round numbers with the help of a place value chart.
Here's the number 217.
If we round this number to the nearest hundred, we need to look at the digit to the right.
In this case, the 1 in the tens place.
Now, let's apply the rounding rule.
Since the number in the tens place is between 1 and 4, we round down.
The number in the hundreds place remains the same,
and the number to the right becomes 0.
217 rounded to the nearest hundred is 200.
Now, let's round to the nearest thousand.
We'll do this without the help of a place value chart this time.
When rounding 7,927 to the nearest thousand,
we look at the digit to the right of the given place value.
In this case, we look at the 9 in the hundreds place.
The rounding rule says that if the digit to the right of the given place value
is between 5 and 9, we round up.
Since 9 is between 5 and 9, we increase the 7 in the thousands place by 1
and the digits to the right become 0.
So, 7,927 rounded to the nearest thousand is 8,000.
Here's a way rounding can help.
Imagine you have a marbles collection of 7,685 marbles.
That's a lot of marbles, but you know you have this exact number
because you keep your marbles in bags of 100.
Your cousin wants to get rid of his marbles, so he gives you 224 marbles.
How many marbles do you have now?
These are pretty big numbers in this equation.
Let's use rounding to estimate how many marbles you have.
Since you keep your marbles in bags of 100, let's round off to the nearest hundred.
When rounding 7,685 to the nearest hundreds place,
we look at the digit to the right of the digit in the hundreds place.
In this case it's 8.
We apply the rule of rounding and know that we must round up, since 8 is 5 or greater.
The number in the hundreds place increases by 1.
In other words, the 6 becomes 7, and the rest of the numbers become 0's.
7,685 rounded to the nearest hundreds is 7,700.
When rounding 224 to the nearest hundreds place,
we look at the digits to the right of the digit in the hundreds place.
In this case, it's 2.
We apply the rule of rounding, and know that we must round down
because 2 is between 1 and 4.
The number in the hundreds place remains the same,
and the rest of the numbers become 0's.
224 rounded to the nearest hundreds is 200.
You know simply by looking at this equation
that you have more than 7,500 marbles, but less than 8,000.
In fact, you estimate 7,900 marbles.
Let's do the math to see if our estimate is close.
7,909 is the answer to this equation.
Our estimate was definitely close.
Wow! That's a lot of marbles.
Be sure not to drop them all.
Rounding gave you a good idea about how many marbles you had
even before you worked out the problem.
As you grow comfortable with rounding,
you can apply the general rule to numbers higher than 1,000.
For now, you can keep practicing with our fun online games and quizzes.
Remember to always be clever.