Why is rounding decimals important

Decimals can be converted to fractions and percentages , which can make it easier to understand their value.

Keep in mind that the placement of each number, where it appears after the decimal. So, if the number was If the number was Decimals are commonly used in our everyday lives, and you probably are capable of adding, subtracting , and rounding decimals in your head without even realizing you're doing it.

We use decimals often when discussing money, weight , and measurements , since decimals can provide us with a precise value. With that said, it's not always necessary to use a decimal in its entirety, whether in daily life or when solving a problem on a test.

Though decimals can technically be infinite, we can utilize the common rounding method to round decimals, making them fit into the problem we're trying to solve. The common rounding method says that if the number you are rounding is followed by the number 5 or above 5,6,7,8,or 9 then you should round that number up.

For example, you can round the number 27 to 30 because 7 is greater than 5. However, the number 24 would be rounded down to 20, because 4 is less than 5. You can round to the nearest ten, as seen above, but you can also round to the nearest hundred or thousand.

For example, 2, can be rounded to the nearest ten 2, the nearest hundred , 2, or the nearest thousand 2, When rounding, you have to start with the number furthest to the right , since each number is used to round the number directly in front of it.

In our example above, consider:. Just like with whole numbers, we use the number directly to the right of each number to round. When rounding decimals, we also want to work our way back from the right. In our original example, So let's try a number that goes a little further out: This number can be rounded in many ways, depending on how precise you need it to be.

At a certain point, the number past the decimal point is so small that it becomes inconsequential, depending on the situation. For example, if this were us weighing a cat, there's no need for us to know that the cat weighs We could safely round this number. However, if this was a scientific measurement of a certain chemical in a blood sample, the longer, more precise number is more useful to scientists, who need their measurements to be as accurate as possible.

On the other hand, knowing our cat is about What if Wendell had decided to round to the nearest ten? He counted sheep, so 9 was in the tens place and that's the last digit that will be kept. The next digit was 2, which is less than 5. So Wendell would've rounded down by keeping the last digit the same and replacing the remaining digit with 0 to get Rounding numbers makes them simpler and easier to use.

Although they're slightly less accurate, their values are still relatively close to what they originally were. People round numbers in many different situations, including many real-world situations you'll find yourself in on a regular basis.

Likewise, you may need an easy way to make simple calculations in your head to determine how many bags of candy you're able to buy at the store. How do you know that? Finally, it's often just easier to work with rounded numbers, because exact numbers aren't only required. If it takes about 25 minutes to get somewhere, it's simply easier to allow yourself 30 minutes of travel time. If you're talking about the population of New York City, it's easier to work with a figure of 8 million people rather than a more exact figure of 8,, people.

Are you ready to add, subtract, multiply, and divide? Don't forget to check out the following activities with a friend or family member:. We're sorry to hear that. Thanks for sticking with us! So glad to hear that! Hope you've been back since then to do some more wondering with us! We are talking about rounding numbers to to the nearest hundred and ten. Some of my classmates include Madison and Stella. We are in third grade and my name is Emory.

Hi, Emory! We really hope that this Wonder added to your discussion with your friends about why we round numbers! Do Madison and Stella know about Wonderopolis? We would love for them to be Wonder Friends, too!! Yep - have have a Wonder about that! Wonder What's the Science of Glass Blowing?

Hi, yesenia! We're thrilled that you read this Wonder! Have you ever rounded numbers before? Hello everyone, was interesting to read your article. Usually i'm reading New York Times , but now i will read you too!

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Follow Twitter Instagram Facebook. Why do we round numbers? What is the most common method to round numbers? How is rounding used in the real world? We were walking through the Wonderopolis pasture the other day when we overheard an interesting conversation between a couple of wolves : Wolf 1: Hey Wayne! That would make me sleepy. Why are you counting them, though? Hide Ads About Ads. Rounding Numbers What is "Rounding"?

Rounding means making a number simpler but keeping its value close to what it was. The result is less accurate, but easier to use. Example: Round 74 to the nearest 10 We want to keep the "7" it is in the 10s position The next digit is "4" which is less than 5, so no change is needed to "7" Answer: 70 74 gets "rounded down". Example: Round 86 to the nearest 10 We want to keep the "8" The next digit is "6" which is 5 or more, so increase the "8" by 1 to "9" Answer: 90 86 gets "rounded up".