Rounding to the Nearest Tenth
Rounding to the nearest tenth is a Grade 6 math skill in Saxon Math, Course 1, Chapter 6 that uses the hundredths digit to decide whether the tenths digit rounds up or stays the same. The rule: look at the digit in the hundredths place (second decimal place). If it is 5 or greater, round the tenths digit up by 1 and drop everything to its right. If it is 4 or less, keep the tenths digit unchanged and drop the rest. For example, 4.68 rounds to 4.7 because the hundredths digit is 8 (≥5). This skill is used in measurement, science data reporting, and estimation throughout middle school math.
Key Concepts
Property To round a decimal to the nearest tenth, you must look at the digit in the hundredths place.
Examples To round to the nearest tenth, we look at the hundredths digit: $10.381 \rightarrow 10.4$, because 8 is 5 or more. $12.345 \rightarrow 12.3$, because 4 is less than 5. $2.375 \rightarrow 2.4$, because 7 is 5 or more.
Explanation Let the hundredths digit be your guide! If this 'boss' digit is a 5 or anything bigger, it tells the tenths digit to 'level up' by one. If the boss is 4 or smaller, it just packs its bags and leaves quietly, letting the tenths digit stay exactly as it was.
Common Questions
How do you round a decimal to the nearest tenth?
Look at the hundredths digit (second digit after the decimal). If it is 5 or more, add 1 to the tenths digit. If it is 4 or less, leave the tenths digit as is. Drop all digits to the right of the tenths place.
Which digit is in the tenths place?
The tenths place is the first digit immediately to the right of the decimal point. In 4.68, the digit 6 is in the tenths place.
Why does the hundredths digit control rounding to the nearest tenth?
Because the hundredths digit tells you how close the number is to the next tenth. A digit of 5–9 means the number is closer to the higher tenth; a digit of 0–4 means it is closer to the lower tenth.
What happens to digits after rounding?
All digits to the right of the rounded place are dropped. In 4.68 rounded to the nearest tenth, the 8 is used to round up the 6, and then the 8 is removed, giving 4.7.
How is rounding to the nearest tenth different from rounding to the nearest whole number?
When rounding to the whole number, you look at the tenths digit to decide. When rounding to the nearest tenth, you look at the hundredths digit. The digit one place to the right of your target always makes the decision.