--- title: "Rounding Decimals: Everything You Need to Know · PrepScholar" description: Struggling with rounding numbers? We explain everything you need to know about rounding decimals and other numbers. image: https://360031.fs1.hubspotusercontent-na1.net/hubfs/360031/pi-1453835_1920.jpg --- **[![PrepScholar](https://www.prepscholar.com/wp-content/uploads/2023/03/PrepScholar-Logo-Colored.png)](https://www.prepscholar.com/)** CALL NOW: [+1 (866) 811-5546](tel:18668115546) [![Start Free Trial](https://no-cache.hubspot.com/cta/default/360031/interactive-171805697634.png)](https://cta-service-cms2.hubspot.com/web-interactives/public/v1/track/redirect?encryptedPayload=AVxigLKJluK2NyG3jpAJh%2F2lClc1fhnVHyMZoQonqRxtJngB8FMX6lc78F84JqOaVAL0d36TA5%2FYuH%2FLCJw8AG3ewREi%2F7a3XDouZgjxWfYCBUge6z76KnSykOxONl3avMK0gUjJGpJdyJE2BDTx8g3bsgHwMtx4Kr9Jfh6Jr7WA2XEIgtLw1OoVvAMo4Kw%3D&webInteractiveContentId=171805697634&portalId=360031) ## Choose Your Test SAT Prep ACT Prep [PrepScholar Advice Blog](https://blog.prepscholar.com/) ☰ - Search Blogs By Category - [SAT](https://blog.prepscholar.com/topic/sat) - [ACT](https://blog.prepscholar.com/topic/act) - [College Admissions](https://blog.prepscholar.com/topic/college-admissions) - [AP and IB Exams](https://blog.prepscholar.com/topic/advanced-placement-ap) - [PSAT](https://blog.prepscholar.com/topic/psat-info-and-strategies) - [TOEFL](https://blog.prepscholar.com/topic/toefl) - [GPA and Coursework](https://blog.prepscholar.com/topic/coursework-gpa) # [Rounding Decimals: Everything You Need to Know](https://blog.prepscholar.com/rounding-decimals-numbers) Posted by [Carrie Cabral](https://blog.prepscholar.com/author/carrie-cabral) | Updated on September 24, 2024 [General Education](https://blog.prepscholar.com/topic/general-education)   ![pi-1453835_1920](https://360031.fs1.hubspotusercontent-na1.net/hub/360031/hubfs/pi-1453835_1920.jpg?width=536&name=pi-1453835_1920.jpg) Most of us are familiar with the concept of **rounding numbers**. We round numbers all the time in our everyday lives, from telling time to taking measurements, since rounding is an easy and helpful way to help us make sense of the numbers around us. But what happens when we encounter decimals? Decimals can be long and unwieldy, and rounding can help make sense of them. Keep reading to find out how to **round decimals**, and how to use the **common method** of rounding.   ## What Is a Decimal? A **decimal** is a system of denoting **integer** and **non-integer** numbers that breaks down into tenths, hundredths, thousands, etc. The number is separated into a **whole number**, which is to the left of a decimal, and the **fraction** is to the right. For example, let's look at the number **10.423**. In this case, 4 is the **tenth**, 2 is the **hundredth** and 3 is the **thousandth**. 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 **10.003** the number would be 10 and 3 thousandth, or **10 3/100**. If the number was **10.03**, it would be **10 3/100**. Using our number above, 10.423, we can break down the number: .4= 4/10 .42= 42/100 .423= 423/100   ![Screen Shot 2019-06-28 at 12.24.20 PM](https://360031.fs1.hubspotusercontent-na1.net/hub/360031/hubfs/Screen%20Shot%202019-06-28%20at%2012.24.20%20PM.png?width=541&name=Screen%20Shot%202019-06-28%20at%2012.24.20%20PM.png) In the U.S. a decimal is denoted by **decimal point**. In some countries, a decimal is actually denoted by a **comma**. Most European countries use a comma, with the exception of the U.K. as well as some South American, Asian, and African countries. Hopefully, you won't run into this issue on tests, but since there's no official international standard on how to write decimals, it's good to know in case you see an unfamiliar number like **10,42**.     ## When Will You Use Decimals? 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.   ## Rounding Numbers: The Common Method 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, 2,367 can be rounded to the nearest **ten** (2,370) the nearest **hundred**, (2,400) or the nearest **thousand** (2,000). 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: 2,36**7** rounds **up** the **6** 2,3**6**7 rounds **up** the **3** 2, **3**67 rounds **down** to **2**.   ![accounting-761599_1920](https://360031.fs1.hubspotusercontent-na1.net/hub/360031/hubfs/accounting-761599_1920.jpg?width=546&name=accounting-761599_1920.jpg)   ## How to Round Decimals 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, 10.423, we know that we could quickly **round down to 10**, since all the numbers following the decimal are **less than 5**, and therefore all round down. So let's try a number that goes a little further out: **14.582354** 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 14.582354 pounds. 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 14.6 pounds is more than enough information. Here's what our number looks like rounding all the way to the tenth:   ![Screen Shot 2019-06-28 at 12.43.37 PM](https://360031.fs1.hubspotusercontent-na1.net/hubfs/360031/Screen%20Shot%202019-06-28%20at%2012.43.37%20PM.png)   ## Knowing When You Should Round Knowing when to round a decimal on a test is tough, and depends on what you're trying to solve for. Most tests will require a precise answer, which is why the decimal was included in the first place. If possible, try to stick with the original number. If rounding will help solve the problem more efficiently, stick at least to the **hundredth**. In a multiple choice situation, you can also look at how the answers are presented. If the answers go to the **thousandth**, you should do your calculations that way as well. Though rounding can be tricky on tests, it's very useful for quick problem solving in everyday life. Say you're at the grocery store, and you're buying a watermelon. The watermelon is **$0.35 per pound.** You weigh your watermelon and it's **20.824 pounds**. You can quickly round up both the pounds and the price, so you can multiply **21 x 0.40** and get a rough idea of how much you'll pay for the watermelon. Remember, the more you round the less precise the number gets, but this allows you to quickly get an idea of the price. We don't need an exact number for the price of our watermelon, but if we were building a desk, for example, it's very important to measure out exactly the right measurement for each leg of the desk. In this situation, there's a big difference between 22.7 inches and 22.9 inches. Always make sure to evaluate how precise you need a number to be before rounding it. Most of us can round up and down in our heads, but always be sure to use the common method of rounding in both everyday and test-taking situations.   ## What's Next? Need more about decimals, fractions, and percentages? Check out [The 3 Steps to Convert Decimals to Fractions (and Back)](https://blog.prepscholar.com/convert-decimal-to-fraction) Looking for the best math test-taking strategies? Get started with this review of [What's Tested On the SAT Math Section](https://blog.prepscholar.com/whats-actually-tested-on-sat-math-topics), and make sure you check out PrepScholar's [Ultimate Math SAT Prep Guide](https://blog.prepscholar.com/sat-math-prep-guide-strategies-tips-practice) to conquer the SAT math section.   [![Looking for help with high school? Our one-on-one online tutoring services can help you study for important exams, review challenging material, or plan out big projects. Get matched with a top tutor who is an expert in the subject you're studying!](https://no-cache.hubspot.com/cta/default/360031/interactive-178532613026.png)](https://blog.prepscholar.com/hs/cta/wi/redirect?encryptedPayload=AVxigLIuBEvL6LPBGEDJNiqtK1GCFO5HjsKjn3EtOs4k65fhRtpPQXwGY8Gc5ltDmZWkHmA2Jed5QYcf96Gu03xNmtLRIsSuTDTfFArUr4GigAUW3zC2fqX8Rn6Nt3KG4VuO3ChS1WnGjhjkmyu8bpRS5jy9TuPy7kuEILZbHom4Kf0uVA%2FCuk1QHFE5LlJjq4%2FhLGc%3D&webInteractiveContentId=178532613026&portalId=360031) ### Trending Now [How to Get Into Harvard and the Ivy League](https://blog.prepscholar.com/how-to-get-into-harvard-and-the-ivy-league-by-a-harvard-alum) [How to Get a Perfect 4.0 GPA](https://blog.prepscholar.com/how-to-get-a-4-0-gpa-and-get-better-grades-by-a-harvard-alum) [How to Write an Amazing College Essay](https://blog.prepscholar.com/how-to-write-a-college-essay) [Should You Take the SAT or ACT?](https://quiz.prepscholar.com/sat-vs-act) [What Exactly Are Colleges Looking For?](https://blog.prepscholar.com/what-do-colleges-look-for) [ACT vs. SAT: 10 Key Differences](https://blog.prepscholar.com/act-vs-sat) [Calculate Your College Chances](https://mycollegechances.prepscholar.com/) Get Your Free **[![PrepScholar](https://www.prepscholar.com/wp-content/uploads/2023/03/PrepScholar-Logo-Colored.png)](https://www.prepscholar.com/)** eBook [5 Tips to Raise Your SAT Score 160+ Points](https://www.prepscholar.com/rp/sat-5-tips-ebook/) [5 Tips to Raise Your ACT Score 4+ Points](https://www.prepscholar.com/rp/act-5-tips-ebook/) ### SAT Prep [Find Your Target SAT Score](https://blog.prepscholar.com/what-is-a-good-sat-score-a-bad-sat-score-an-excellent-sat-score) [Free Complete Official SAT Practice Tests](https://blog.prepscholar.com/complete-official-sat-practice-tests-free-links) ### **[How to Get a Perfect SAT Score, by an Expert Full Scorer](https://blog.prepscholar.com/how-to-get-a-perfect-sat-score-by-a-2400-sat-scorer)** [Score 800 on SAT Math](https://blog.prepscholar.com/how-to-get-800-on-sat-math-by-a-perfect-scorer) [Score 800 on SAT Reading and Writing](https://blog.prepscholar.com/how-to-get-800-on-sat-reading-and-writing) [Raise Your SAT Score by 160+ Points GUARANTEED. Start Your 5-Day Risk-Free Trial](https://www.prepscholar.com/sat-test-prep/?utm_source=databasepage&utm_medium=sidebar&utm_campaign=sat_guarantee) ### ACT Prep [Find Your Target ACT Score](https://blog.prepscholar.com/what-is-a-good-act-score-a-bad-act-score-an-excellent-act-score) [Complete Official Free ACT Practice Tests](https://blog.prepscholar.com/complete-official-act-practice-tests-free-links) ### **[How to Get a Perfect ACT Score, by a 36 Full Scorer](https://blog.prepscholar.com/how-to-get-a-perfect-act-score-by-a-36-full-scorer)** [Get a 36 on ACT English](https://blog.prepscholar.com/how-to-get-36-on-act-english-9-strategies-from-a-perfect-scorer) [Get a 36 on ACT Math](https://blog.prepscholar.com/how-to-get-36-on-act-math-8-strategies-by-a-perfect-scorer) [Get a 36 on ACT Reading](https://blog.prepscholar.com/how-to-get-36-on-act-reading-11-strategies-from-a-perfect-scorer) Stay Informed Get the latest articles and test prep tips! - [![Follow us on Facebook (icon)](https://360031.fs1.hubspotusercontent-na1.net/hubfs/360031/facebook_logo.png)](https://www.facebook.com/prepscholar) - [![Follow us on X (icon)](https://360031.fs1.hubspotusercontent-na1.net/hubfs/360031/twitterx-50.png)](https://twitter.com/intent/follow?region=follow_link&screen_name=PrepScholar&tw_p=followbutton) - [![Follow us on Instagram (icon)](https://360031.fs1.hubspotusercontent-na1.net/hubfs/360031/instagram-sidebar.webp)](https://www.instagram.com/prepscholar/) Get Exclusive Tips for College Admissions Sign up to receive free guidance on everything from acing the SAT to writing a standout college admissions essay. × ## Thanks for Subscribing! ![Check icon](https://360031.fs1.hubspotusercontent-na1.net/hub/360031/file-2386656898.png/subscribe_check.png.png?width=175&name=subscribe_check.png) To receive immediate updates on all our helpful guides and strategies, **follow us** on social media: [![Facebook](https://blogprepschola.wpenginepowered.com/wp-content/uploads/2025/03/26de6c2beb2b71ee5b8d660200359259.png)](https://www.facebook.com/prepscholar) [![X](https://blogprepschola.wpenginepowered.com/wp-content/uploads/2025/03/f233666501ea25d3fcf3c390d2f08c7b.png)](https://x.com/intent/follow?region=follow_link&screen_name=PrepScholar&tw_p=followbutton) [![LinkedIn](https://blogprepschola.wpenginepowered.com/wp-content/uploads/2025/03/linkedin.png)](https://www.linkedin.com/company/prepscholar/) [![Instagram](https://blogprepschola.wpenginepowered.com/wp-content/uploads/2025/03/download-1.png)](https://www.instagram.com/prepscholar/) **Have friends who also need help with test prep?** Share this article! [![Share on email](https://360031.fs1.hubspotusercontent-na1.net/hub/360031/hubfs/email-color.png?width=24&name=email-color.png)](mailto:?subject=Check%20out%20https%3A%2F%2Fblog.prepscholar.com%2Frounding-decimals-numbers%3Futm_medium%3Dsocial%26utm_source%3Demail%20&body=Check%20out%20https%3A%2F%2Fblog.prepscholar.com%2Frounding-decimals-numbers%3Futm_medium%3Dsocial%26utm_source%3Demail) [![Share on facebook](https://360031.fs1.hubspotusercontent-na1.net/hub/360031/hubfs/facebook-color.png?width=24&name=facebook-color.png)](http://www.facebook.com/share.php?u=https%3A%2F%2Fblog.prepscholar.com%2Frounding-decimals-numbers%3Futm_medium%3Dsocial%26utm_source%3Dfacebook) [![Share on twitter](https://360031.fs1.hubspotusercontent-na1.net/hub/360031/hubfs/x-twitter-color.png?width=24&name=x-twitter-color.png)](https://twitter.com/intent/tweet?original_referer=https%3A%2F%2Fblog.prepscholar.com%2Frounding-decimals-numbers%3Futm_medium%3Dsocial%26utm_source%3Dtwitter&url=https%3A%2F%2Fblog.prepscholar.com%2Frounding-decimals-numbers%3Futm_medium%3Dsocial%26utm_source%3Dtwitter&source=tweetbutton&text=) [![Share on linkedin](https://360031.fs1.hubspotusercontent-na1.net/hub/360031/hubfs/linkedin-color.png?width=24&name=linkedin-color.png)](http://www.linkedin.com/shareArticle?mini=true&url=https%3A%2F%2Fblog.prepscholar.com%2Frounding-decimals-numbers%3Futm_medium%3Dsocial%26utm_source%3Dlinkedin) About the Author Carrie holds a Bachelors in Writing, Literature, and Publishing from Emerson College, and is currently pursuing an MFA. She worked in book publishing for several years, and believes that books can open up new worlds. She loves reading, the outdoors, and learning about new things. ## Ask a Question Below Have any questions about this article or other topics? Ask below and we'll reply! **[![PrepScholar](https://www.prepscholar.com/wp-content/uploads/2023/03/PrepScholar-Logo-White.png)](https://www.prepscholar.com)** - [WHO WE ARE](https://www.prepscholar.com/who-we-are/) - [SUCCESS STORIES](https://www.prepscholar.com/case-studies/) - [ADVICE BLOG](https://blog.prepscholar.com/) - [FOR SCHOOLS](https://www.prepscholar.com/for-schools/) - [SAT](https://www.prepscholar.com/sat-test-prep/) - [ACT](https://www.prepscholar.com/act-test-prep/) - [PSAT](https://www.prepscholar.com/psat-test-prep/) - [AP](https://www.prepscholar.com/ap-tutoring/) - [GRE](https://www.prepscholar.com/gre-test-prep/) - [GMAT](https://www.prepscholar.com/gmat-test-prep/) - [TOEFL](https://www.prepscholar.com/toefl-test-prep/) - [ADMISSIONS](https://www.prepscholar.com/college-admissions-consulting/) - [TERMS OF SERVICE](https://www.prepscholar.com/terms-of-service/) - [PRIVACY POLICY](https://www.prepscholar.com/privacy-policy/) - [![follow us on X (icon)](https://cdn2.hubspot.net/hubfs/360031/twitter-64.png)](https://twitter.com/intent/follow?region=follow_link&screen_name=PrepScholar&tw_p=followbutton) - [![Follow us on Facebook (icon)](https://cdn2.hubspot.net/hubfs/360031/facebook-64.png)](https://www.facebook.com/prepscholar) - [![follow us on Instagram (icon)](https://360031.fs1.hubspotusercontent-na1.net/hubfs/360031/instagram-64.svg)](https://www.instagram.com/prepscholar/) - [![follow us on TikTok (icon)](https://360031.fs1.hubspotusercontent-na1.net/hubfs/360031/tiktok-50.svg)](https://www.tiktok.com/@prepscholarofficial) - [![Follow us on LinkedIn (icon)](https://360031.fs1.hubspotusercontent-na1.net/hubfs/360031/linkedin50.png)](https://www.linkedin.com/company/prepscholar/) © PrepScholar 2013-2025. All rights reserved SAT® is a registered trademark of the College Entrance Examination BoardTM. The College Entrance Examination BoardTM does not endorse, nor is it affiliated in any way with the owner or any content of this web site. ACT® is a registered trademark belonging to ACT Education Corporation ("ACT"). ACT is not involved with or affiliated with PrepScholar Inc., nor does ACT endorse or sponsor any of the products or services offered by PrepScholar Inc. GRE® and TOEFL® are registered trademarks of the ETS®. The ETS® does not endorse, nor is it affiliated in any way with, the owner or any content of this web site. GMAT® is a registered trademark of the Graduate Management Admissions Council®. The Graduate Management Admissions Council® does not endorse, nor is it affiliated in any way with, the owner or any content of this website. ```json { "@context" : "https://schema.org", "@type" : "BlogPosting", "author" : { "@type" : "Person", "name" : "Carrie Cabral", "url" : "https://blog.prepscholar.com/author/carrie-cabral" }, "dateModified" : "2024-09-24T20:17:04+00:00", "datePublished" : "2019-08-13T21:00:00+00:00", "description" : "Struggling with rounding numbers? We explain everything you need to know about rounding decimals and other numbers.", "headline" : "Rounding Decimals: Everything You Need to Know", "image" : "https://cdn2.hubspot.net/hubfs/360031/pi-1453835_1920.jpg", "mainEntityOfPage" : { "@id" : "https://blog.prepscholar.com/rounding-decimals-numbers", "@type" : "WebPage" }, "publisher" : { "@type" : "Organization", "logo" : { "@type" : "ImageObject", "url" : "https://www.prepscholar.com/wp-content/uploads/2023/03/PrepScholar-Logo-Colored.png" }, "name" : "PrepScholar" } } ```