Rounding to the Nearest 10 | Lesson + Practice

Welcome to Math with Mr. J. In this video, I'm going to cover how to round to the nearest 10. We'll go through some examples of rounding two-digit numbers, and then we'll move on to three-digit numbers. After we go through some examples together, I'll give you some practice problems that you can try on your own. Remember, when we round, we find a number that's close to the original number, but easier to work with. Sometimes we don't need an exact answer. We just need a quick estimate. So we can use rounding. Let's jump into number one, where we have 68. We are rounding to the nearest 10. So is 68 closer to 60 or 70? The first thing that we need to do when rounding is find the place we are rounding to. Again, we are rounding to the nearest 10. So we are rounding to the 10's place. Let's underline the digit in the 10's place. That's this 6 right here. Now we look to the right of the place we are rounding to. The digit to the right will tell us if we round up or round down. Basically, the digit to the right tells us which 10 we are closer to here. 60 or 70. Let's actually draw an arrow showing that we need to look 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. And this rhyme can help us remember this. 5 or more, raise the score. 4 or less, let it rest. Now 8 is 5 or more. So we raise the score. That means we add 1 to the digit in the rounding place. We add 1 to the 6 in the 10's place. So the 6 changes to a 7. We round up. And we need a 0 in the 1's place. We round up to 70. 68 is closer to 70 than it is to 60. So 68 rounds to 70 when rounded to the nearest 10. 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. 68 is not equal to 70. So we can't use an equal sign here. Instead, we use the approximate symbol to show that we rounded. Moving on to number 2, we have 32. Let's round to the nearest 10. So is 32 closer to 30 or 40? First, let's underline the digit in the place we are rounding to, the 10's place. We have a 3 here. Now we need to look at the digit to the right. And that digit will tell us if we round up or down. We have a 2 to the right. Is 2 5 or more? Or 4 or less? 2 is 4 or less. 4 or less? Let it rest. That means the digit in the place we are rounding to stays the same. And we round down. So that 3 stays the same. And then we need a 0 in the 1's place. We round down to 30. 32 is closer to 30 than it is to 40. 32 rounds to 30. Moving on to number 3, we have 55. We need to round to the nearest 10. Let's start by underlining the digit in the place we are rounding to. That's going to be this 5 in the 10's place. Now let's look at the digit to the right. We have a 5. 5 is 5 or more. So we raise the score. We add 1 to the digit in the rounding place. We round up. So the 5 in the 10's place is now a 6. And we need a 0 in the 1's place. We round up to 60 here. 55 rounds to 60. Now 55 is exactly halfway between 50 and 60. So it's the same distance from both. But remember, whenever we have something exactly halfway between, we always round up. Lastly, for number 4, we have 84. Let's round this to the nearest 10. So we'll underline the digit in the 10's place. This 8 right here. Now we need to look at the digit to the right. We have a 4. 4 is 4 or less. So we let it rest. The digit in the place we are rounding to stays the same. And we round down. So 8 stays the same. And then we need a 0 in the 1's place. So we round down to 80. 84 rounds to 80. 84 is closer to 80 than it is to 90. So there's how to round 2-digit numbers to the nearest 10. Let's move on to 3-digit numbers. Now let's take a look at rounding 3-digit numbers to the nearest 10. Let's jump into number 1, where we have 126. We are rounding to the nearest 10 here. So is this closer to 120 or 130? The first thing that we need to do is find the place we are rounding to. Again, we are rounding to the nearest 10. So we are rounding to the 10's place. Let's underline the digit in the 10's place. That's this 2 right here. Now we look to the right of the place we are rounding to. Basically, the digit to the right tells us which 10 we are closer to here. 120 or 130. Now 6 is 5 or more. So we raise the score. We round up. We need to add 1 to the digit in the rounding place. The 2 in the 10's. So the 2 changes to a 3. So we have our 1 in the 100's place. And then that 2 changes to a 3. And we need a 0 in the 1's place. We round up to 130 here. 126 is closer to 130 than it is to 120. 126 rounds to 130 when we round to the nearest 10. Moving on to number 2, we have 543. Let's round this to the nearest 10. So it's 543 closer to 540 or 550. First, let's underline the digit in the place we are rounding to. The 10's place. We have a 4 in the 10's place. Next, we need to look at the digit to the right. We have a 3 to the right. 3 is 4 or less. 4 or less, let it rest. That means the digit in the place we are rounding to stays the same. And we round down. So we have a 5 in the 100's place. And then the 4 in the 10's place stays the same. Then we need a 0 in the 1's place. So we round down to 540. 543 is closer to 540 than it is to 550. So 543 rounds to 540 when we round to the nearest 10. Moving on to number 3, we have 764. Let's round this to the nearest 10. We'll start by underlining the digit in the place we are rounding to. The 10's place. We have a 6 in the 10's place. Now we look at the digit to the right. We have a 4. 4 is 4 or less. So we let it rest. The digit in the place we are rounding to stays the same. And we round down. So we keep that 7 in the 100's place. And then 6 stays the same. Then we need a 0 in the 1's place. So we round down to 760. So 764 rounds to 760 when we round to the nearest 10. Lastly, let's move on to number 4 where we have 387. Let's round to the nearest 10. So is this closer to 380 or 390? Let's start by underlining the digit in the place we are rounding to. So we need to underline the digit in the 10's place. This 8. Now we look at the digit to the right. We have a 7. Is that 5 or more? Or 4 or less? 7 is 5 or more. So we raise the score. We round up. That means we add 1 to the digit in the rounding place. The 8 changes to a 9. So we keep that 3 in the 100's place. And then the 8 in the 10's place changes to a 9. And then we need a 0 in the 1's place. We round up to 390 here. So 387 rounds to 390 when we round to the nearest 10. 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 10. I'll give you 4 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 4 minutes. Let's go over the answers. So here are our answers. For number 1, we should have 50. For number 2, 20. For number 3, 60. For number 4, 80. For number 5, 320. For number 6, 660. For number 7, 790. And then lastly, for number 8, 830. So there you have it. There's how to round to the nearest 10. I hope that helped. Thanks so much for watching. Until next time, peace.