---
title: "Rounding decimals (age 9+)"
description: "Round decimals with two decimal places to the nearest whole number and to one decimal place"
canonical: https://lightmysky.com/learn/mathematics/rounding-decimals-age-9-mt_Ii1hV4V5ql
source: https://lightmysky.com/learn/mathematics/rounding-decimals-age-9-mt_Ii1hV4V5ql.md
retrieved: 2026-09-12
---

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# Rounding decimals (age 9+)

Round decimals with two decimal places to the nearest whole number and to one decimal place

Subject: Mathematics · Area: Fractions · Ages 9 to 10
Page: https://lightmysky.com/learn/mathematics/rounding-decimals-age-9-mt_Ii1hV4V5ql

## Ready when they can

- Round 3.47 to the nearest whole number (3) and to 1 d.p. (3.5)
- Round 12.95 to 1 d.p. (13.0) and explain the boundary case
- Estimate 4.83 + 2.17 by rounding each to the nearest whole number

## Lesson: Rounding decimals

To round a decimal to the nearest whole number, look at the tenths digit. That is the first digit after the decimal point. If it is 5 or more, round up. If it is less than 5, keep the whole number the same.

**Example.** 3.47 has a 4 in the tenths place. Four is less than five, so 3.47 rounds down to 3.

Rounding to one decimal place works the same way, but you check one digit further: the hundredths digit. That is the second digit after the point.

*(drawing: 12.95 has a 5 in the hundredths place, so the 9 rounds up. That turns 12.95 into 13.0.)*

**Tip.** When you estimate a sum, round each decimal to the nearest whole number first, then add. 4.83 rounds to 5, and 2.17 rounds to 2, so the estimate is 5 + 2 = 7.

**Recap.** Check the digit right after the place you are rounding to: 5 or more rounds up, below 5 stays the same.

## Practice

15 questions on this page, each with its working shown.

## Needs first

- [Rounding decimals to whole numbers](https://lightmysky.com/learn/mathematics/rounding-decimals-to-whole-numbers-mt_Fl7b8q9pI1)

## Opens up

- [Decimals to three places](https://lightmysky.com/learn/mathematics/decimals-to-three-places-mt_sA2OvTiech)