---
title: "Reading and writing numbers (age 10+)"
description: "Read, write, and compare decimals to thousandths using base-ten numerals, number names, and expanded form; compare using >, =, < based on place-value meaning"
canonical: https://lightmysky.com/learn/mathematics/reading-and-writing-numbers-age-10-mt_Ac7oMWhyPw
source: https://lightmysky.com/learn/mathematics/reading-and-writing-numbers-age-10-mt_Ac7oMWhyPw.md
retrieved: 2026-10-19
---

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# Reading and writing numbers (age 10+)

Read, write, and compare decimals to thousandths using base-ten numerals, number names, and expanded form; compare using >, =, < based on place-value meaning

Subject: Mathematics · Area: Number Representation & Place Value · Ages 10 to 11
Page: https://lightmysky.com/learn/mathematics/reading-and-writing-numbers-age-10-mt_Ac7oMWhyPw

## Ready when they can

- Write 347.392 in expanded form: 3×100 + 4×10 + 7×1 + 3×(1/10) + 9×(1/100) + 2×(1/1000)
- Compare 0.372 and 0.38 using place-value reasoning
- Write 'five and sixty-two thousandths' as 5.062

## Lesson: Reading and writing decimals to thousandths

You already know tenths, hundredths and thousandths from the stall board and the rain gauge. Now you will read bigger numbers that have whole ones as well as tiny parts. To the left of the point the names stay as they always were: ones, tens, hundreds, growing outwards. To the right, each new place stands for a value ten times smaller than the one before it.

*(drawing: Moving right from the ones place, each column is ten times smaller: tenths, then hundredths, then thousandths.)*

**Example.** Look at 528.416. The 4 right after the decimal point is 4 tenths, or 0.4. The 1 is 1 hundredth, or 0.01. The 6 is 6 thousandths, or 0.006.

Expanded form adds up the value of every digit: 5x100 + 2x10 + 8x1 + 4x(1/10) + 1x(1/100) + 6x(1/1000) makes 528.416. Each part names one place, and the fraction in it tells you which place.

Word names work the same way. 'And' marks the decimal point, so 'two and forty-seven thousandths' means 2 ones plus 47 thousandths, written as 2.047. There are no tenths in it, so a 0 holds that spot.

To compare decimals, line up the decimal points and check one place at a time, starting from the biggest place. 0.451 and 0.46 tie at 4 tenths, but 0.46 has 6 hundredths while 0.451 only has 5, so 0.46 is larger. Writing 0.46 as 0.460 first lines the places up, and a zero on the end never changes the value.

**Recap.** Read decimals by place value, use 'and' for the decimal point in words, and compare digit by digit starting from the largest place.

## Practice

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

## Needs first

- [Comparing Decimals](https://lightmysky.com/learn/mathematics/comparing-decimals-mt_933BohS9BH)
- [Place Value × 10 and ÷ 10](https://lightmysky.com/learn/mathematics/place-value-10-and-10-mt_EDgw64OmfA)
- [Reading and writing numbers (age 9+)](https://lightmysky.com/learn/mathematics/reading-and-writing-numbers-age-9-mt_JwP9QFv6gQ)
- [Thousandths (age 9+)](https://lightmysky.com/learn/mathematics/thousandths-age-9-mt_kdWoAel3Zl)

## Opens up

- [Rounding to a required degree of accuracy](https://lightmysky.com/learn/mathematics/rounding-to-a-required-degree-of-accuracy-mt__casygEB85)
- [Addition and subtraction strategies (age 10+)](https://lightmysky.com/learn/mathematics/addition-and-subtraction-strategies-age-10-mt_JH_6RpNWjr)
- [Reading Decimal Places](https://lightmysky.com/learn/mathematics/reading-decimal-places-mt_lNGpnILM5C)