Rounding to the Nearest 100 | Lesson + Practice

Welcome to Math with Mr. J. In this video, I'm going to cover how to round to the nearest hundred. We'll go through some examples of rounding three-digit numbers, and then we'll move on to four-digit numbers. After we go through some examples together, I'll give you some practice problems that you can try on your own. Let's jump into number one, where we have 438. Now, when we round to the nearest hundred, we're finding the closest hundred. So, 100, 200, 300, and so on. All of the numbers we get when we count up by hundreds. So, for number one here, we need to figure out which hundred 438 is closer to, 400 or 500. The first thing that we need to do is find the place we are rounding to. We are rounding to the nearest hundred, so we are rounding to the hundreds place. Let's underline the digit in the hundreds place, this 4 right here. Now, we look to the right of that place. The digit to the right will tell us if we round up or down. Basically, the digit to the right will tell us which hundred we are closer to here, 400 or 500. Let's actually draw an arrow to show that we are looking at the digit to the right. And that brings us to our rounding rules. If the digit to the right is 5 or more, we round up. If the digit to the right is 4 or less, we round down. We can think 5 or more, raise the score, or 4 or less, let it rest. And that can help us remember this. Now, our digit to the right, 3, is 4 or less. 4 or less, let it rest. That means the digit in our rounding place, the 4 in the hundreds, stays the same, and we round down. So that 4 stays the same, and this rounds to 400. So again, that 4 stays the same, and then the digits to the right of the hundreds place become zeros. 438 is closer to 400 than it is to 500. 438 rounds to 400 when rounding to the nearest hundred. Now, before moving on to number 2, I do want to mention the squiggly equal sign here. This is the approximate symbol. And we can use it when rounding. This tells us we have a number that's close, but not exact. 438 isn't equal to 400, so we can't use an equal sign. Instead, we use the approximate symbol to show that we rounded. So something to keep in mind. Let's move on to number 2, where we have 193. Let's round to the nearest hundred. So is this closer to 100 or 200? We'll start by underlining the digit in the hundreds place. This 1 right here. Now we need to look at the digit to the right. And this will tell us if we round up or down. 9 is 5 or more, so we need to raise the score. We need to round up. So we need to add 1 to the digit in our rounding place. That's the 1 in the hundreds place. So that 1 rounds up. It changes to a 2. And this rounds to 200. We have our 2 in the hundreds place, and then the digits to the right become zeros. 193 rounds to 200 when rounded to the nearest hundred. Moving on to number 3, we have 564. Let's round to the nearest hundred. So is this closer to 500 or 600? And we'll start by underlining the digit in the hundreds place. This 5 right here. Now we need to look to the right to see if we round up or down. We have a 6. 6 is 5 or more, so we round up. We raise the score. So we need to add 1 to the digit in the rounding place. The 5 in the hundreds. So the 5 changes to a 6. And then the digits to the right of the hundreds place become zeros. This rounds to 600. So 564 rounds to 600 when rounded to the nearest hundred. Lastly, let's move on to number 4, where we have 827. Let's round to the nearest hundred. Is this closer to 800 or 900? We'll start by underlining the digit in the hundreds place. This 8. Now we need to look to the right. We have a 2 to the right. That's 4 or less. So we let it rest. That means the digit in the hundreds place stays the same. And we round down. So that 8 stays the same in the hundreds place. And then the digits to the right of the hundreds place become zeros. This rounds down to 800. 827 rounds to 800 when rounded to the nearest hundred. So there's how to round 3-digit numbers to the nearest hundred. Let's move on to 4-digit numbers. Now let's take a look at rounding 4-digit numbers to the nearest hundred. Let's jump into number 1, where we have 5295. So for number 1 here, we need to figure out which hundred 5295 is closer to. 5200 or 5300? The first thing that we need to do is find the place we are rounding to. We are rounding to the nearest hundred. So we are rounding to the hundreds place. Let's underline the digit in the hundreds place. That's going to be this 2 right here. Now we look to the right of that place we are rounding to. Basically, that digit to the right will tell us which hundred we are closer to here. 5200 or 5300? Our digit to the right, 9, is 5 or more. 5 or more raise the score. So we round up here. We need to add 1 to the digit in the rounding place. The 2 in the hundreds. So the 2 changes to a 3. So we have 5000. We keep that 5 in the thousands place. And then the 2 in the hundreds place rounds up to a 3. And the digits to the right of the hundreds place become zeros. 5295 is closer to 5300 than it is to 5200. So 5295 rounds to 5300 when we round to the nearest hundred. Moving on to number 2. We have 2716. Let's round to the nearest hundred. So is this closer to 2700 or 2800? We'll start by underlining the digit in the hundreds place. So this 7 right here. Next, we need to look at the digit to the right. Our digit to the right, 1, is 4 or less. 4 or less, let it rest. That means the digit in our rounding place, the 7 in the hundreds, stays the same. And we round down. So we keep that 2 in the thousands place. And then the 7 in the hundreds place stays the same. We round it down. And then the digits to the right of the hundreds place become zeros. So we round down to 2700. 2716 is closer to 2700 than it is to 2800. So 2716 rounds to 2700 when rounded to the nearest hundred. Moving on to number 3. We have 6382. Let's round to the nearest hundred here. We'll start by underlining the digit in the hundreds place. This 3 right here. Now we need to look to the right. We have an 8. 8 is 5 or more. So we need to raise the score. We need to round up. So we need to add 1 to the digit in our rounding place, the 3 in the hundreds. So that 3 is going to change to 4. So we keep that 6 in the thousands place. And then the 3 in the hundreds is now a 4. And the digits to the right of the hundreds place become zeros. So this rounds up. So 6382 rounds to 6400 when rounded to the nearest hundred. Lastly, let's move on to number 4 where we have 9647. Let's round to the nearest hundred. So we'll underline the digit in the hundreds place. That 6 right there. Now we need to look at the digit to the right to see if we round up or down. We have a 4 to the right. Is 4 5 or more or 4 or less? 4 is 4 or less. So we let it rest here. We round down. The 6 in the hundreds is going to stay the same. So we keep that 9 in the thousands place. And then the 6 in the hundreds stays the same. We're rounding down. And then the digits to the right of the hundreds place become zeros. So 9647 rounds to 9600 when rounded to the nearest hundred. Now that we've gone through some examples together, it's time for you to try some practice problems on your own. So have paper and a pencil ready. So here are your practice problems. Round each number to the nearest hundred. I'll give you four minutes and then we will go over the answers. Feel free to pause if you need more time or jump ahead to the answers whenever you are ready. Go ahead and start. Okay, so that was four minutes. Let's go over the answers. So here are our answers. For number 1, we should have 100. For number 2, 800. For number 3, 400. For number 4, 500. For number 5, 3,700. For number 6, 1,100. For number 7, 8,800. And then lastly, for number 8, 2,400. So there you have it. There's how to round to the nearest hundred. I hope that helped. Thanks so much for watching. Until next time, peace.