In order to round to one decimal place, you must be familiar with the concept of rounding numbers. You also need to know the names of each decimal place that lie to the right of the decimal point. In this article, we'll explain these terms and show you two ways to round to the first decimal.
How to Round to One Decimal Place
Each place value, or number of decimal places to the right of the decimal point, has a different name. The diagram below labels the names of each place value:
When you round to the first decimal place, or to the nearest tenth, the number in the hundredth point place will determine whether you round up or down. If the hundredths digit is a number between 5 and 9, round up to the nearest whole number. If it's a number between 0 and 4, you would "round down" by keeping the tenths place the same.
The number below is rounded to the hundredths place. Let's determine if we need to round up or down in order to round to the nearest tenth:
Since the number in the hundredths place is 6, which is between 5 and 9, we would round the tenth decimal point up to 9. The resulting number from rounding to nearest tenth should be:
Rounding from the Thousandths Place
Let's learn how to decrease decimals from the thousandths place to the tenths place. To do this, we must first round to the nearest hundredth:
The number in the thousandths place is 3, which means that we would round down the second decimal place by keeping it the same:
Since the number in the hundredths place is 9, we will round up the tenth decimal point to 3. The resulting number from rounding to nearest tenth should be:
Why Round to One Decimal Place?
It's important to know how to round to one decimal place because some numbers go on for several decimal places. So to keep things concise, you need to round down to one decimal place. When you understand the difference between rounding to the nearest tenth, hundredth, and thousandths and know whether to round up or down, you've mastered the art of rounding to one decimal place.