Chapter 2 of 6

33%

Tamil Nadu (TNBSE)Class 5 Mathematics★ 10-12 marks across TN Class 5 exams — 5-6 digit numbers, multiplication 3-digit×2-digit, division 4-digit÷2-digit, factors and multiples

Numbers

Samacheer Kalvi (TN State Board) Class 5 Mathematics — Chapter 2, Numbers. Large numbers, HCF, LCM, fractions and decimals. Study notes, key concepts, worked examples, practice questions and quick revision for exam preparation.

⏱ 12 min readMedium difficulty✓ Free · NCERT-aligned

Worksheet

Podcast

Listen as a conversation

A teacher & a student talk through the chapter — in your language.

Mind Map

The chapter at a glance

Every concept and exam-favourite branch — revisable in 5 minutes.

…

Study Guide

Night-before notes

Key points, glossary and the questions most likely to show up.

…

VocabularyBuild your vocabularyLexiGenome mines the key words and schedules them with spaced repetition.Mine words →

By the end of this chapter you'll be able to…

1Read, write up to 6-digit numbers; understand Indian place value (lakhs, ten thousands)
2Multiply 3-digit by 2-digit (456×32)
3Divide 4-digit by 2-digit (3456÷24)
4Find factors and multiples; identify prime and composite numbers
5Find HCF by listing factors and LCM by listing multiples

💡

Why this chapter matters

Class 5 Numbers is the culminating arithmetic chapter of primary school. Children work with 5-6 digit numbers (up to lakhs), multiply 3-digit by 2-digit, divide 4-digit by 2-digit, and learn factors/multiples and HCF/LCM. This is the bridge to middle school mathematics.

Before you start — revise these

A 5-minute refresher here will save you 30 minutes of confusion below.

🔗

Numbers — Class 5 Mathematics (Samacheer Kalvi)

TN State Board (Samacheer Kalvi) Class 5 Mathematics, Chapter 2. Large numbers, HCF, LCM, fractions and decimals.

1. About this chapter

This chapter covers Numbers as part of the Class 5 Samacheer Kalvi Mathematics curriculum. It deals with large numbers, hcf, lcm, fractions and decimals and builds conceptual understanding essential for the TN School Term Exam.

By the end of this chapter, students will be able to:

Read and write large numbers
Find HCF and LCM
Add and subtract fractions and decimals

2. Key concepts

Concept 1: Read and write large numbers.
Concept 2: Find HCF and LCM.
Concept 3: Add and subtract fractions and decimals.

3. Important terms and formulas

Term / Formula	Description
Read and write large…	Read and write large numbers
Find HCF and LCM…	Find HCF and LCM
Add and subtract fractions…	Add and subtract fractions and decimals

4. Worked examples

Example 1. Applying a key concept from this chapter.

Solution: Identify the relevant principle → apply the formula or rule → state the answer with correct units.

Example 2. A typical exam-style question on numbers.

Solution: Break the problem into steps, use the appropriate formula and verify the answer.

5. Common mistakes

Mistake: Skipping units or forgetting to state them. Fix: Always write units alongside every quantity and answer.
Mistake: Confusing similar terms or concepts in this chapter. Fix: Make a comparison table of the terms during revision.

6. Practice (exam-style)

Define the main term or principle covered in Chapter 2.
Give two real-life examples related to numbers.
Solve a short numerical or descriptive question from this chapter.
State one important formula and explain each symbol.

7. Answer key (hints)

Refer to section 2 (Key concepts) above for the definition.
Examples should be drawn from daily experience and local context.
Apply the formula from section 3, show all steps clearly.
Formula with units — refer to the textbook glossary for symbol meanings.

8. Quick revision

Class 5 Mathematics — Chapter 2: Numbers.
Core idea: Large numbers, HCF, LCM, fractions and decimals.
Key outcomes: Read and write large numbers; Find HCF and LCM; Add and subtract fractions and decimals.
Always revise diagrams / tables from the Samacheer Kalvi textbook before the exam.

Key formulas & results

Everything you need to memorise, in one card. Screenshot this for revision.

Factors and Multiples

Factors of 12: 1,2,3,4,6,12 (all numbers that divide 12 exactly). Multiples of 12: 12,24,36,48,… (12×1,×2,×3,…). Prime: only 2 factors (2,3,5,7,11,13,…). Composite: more than 2 factors (4,6,8,9,10,12,…). 1 is neither.

Every number is a factor of itself. 1 is a factor of every number. The smallest prime is 2 (the only even prime).

AI helpers for this chapter

Generate more practice on the fly, or have the chapter explained at a different level.

⚡

Generate 5 more questions

Fresh MCQs + short-answer items based on this chapter, plus answer keys.

🧠

Explain at a different level

Re-explain the chapter at the level you actually want.

📝 My notes

Saved on this device — sign in to sync · how this works

0/600

Practice more, ask doubts, find a tutor

Tamil Nadu (TNBSE) Class 5 mock tests

Tamil Nadu (TNBSE) Class 5 PYQs

Ask in Q&A

Mathematics flashcards

Related chapters

Students who read Numbers usually read these next.

Geometry

Samacheer Kalvi (TN State Board) Class 5 Mathematics — Chapter 1, Geometry. Polygons, nets and 3D shapes. Study notes, key concepts, worked examples, practice questions and quick revision for exam preparation.

Patterns

Samacheer Kalvi (TN State Board) Class 5 Mathematics — Chapter 3, Patterns. Sequences and basic algebraic thinking. Study notes, key concepts, worked examples, practice questions and quick revision for exam preparation.

Measurements

Samacheer Kalvi (TN State Board) Class 5 Mathematics — Chapter 4, Measurements. Perimeter, area and introductory volume. Study notes, key concepts, worked examples, practice questions and quick revision for exam preparation.

Interconcept

Samacheer Kalvi (TN State Board) Class 5 Mathematics — Chapter 5, Interconcept. Connecting mathematical ideas. Study notes, key concepts, worked examples, practice questions and quick revision for exam preparation.

🧑‍🏫