The World of Numbers Class 9 Maths NCERT Solutions

The NCERT Solutions Class 9 Maths Chapter 3 The World of Numbers solve every question from the new Ganita Manjari book. This is the third chapter of the 2026-27 syllabus. It takes you from integers and debts to rational numbers, their order on the line, and decimal expansions.

• Exercises solved: Exercise 3.1 to 3.5 and all 16 End-of-Chapter problems
• Main skills: adding integers, ordering rational numbers, and reading terminating or repeating decimals
• Why it matters: it sets the number-system base for Class 10 real numbers

These solutions are prepared by subject teachers, matched to the current 2026-27 NCERT, and checked step by step so a Class 9 student can follow each line.

What Does Class 9 Maths Chapter 3 The World of Numbers Cover?

The chapter grows the number line one step at a time. It starts with integers, using trade stories of credit and debt to show why negative numbers are needed. It then moves to rational numbers, how to add them, and how to place them in order. The NCERT Solutions Class 9 Maths Chapter 3 The World of Numbers finish with decimal expansions, showing when a fraction ends and when it repeats.

Video Walkthrough

Source: Vedantu CBSE 10th on YouTube

Class 9 Maths Chapter 3 The World of Numbers Exercise-Wise Breakdown

The chapter has five exercise sets and one long End-of-Chapter set. The table below shows what each part asks, so you can plan your practice.

Common Mistakes Students Make in The World of Numbers

Most errors in this chapter come from sign slips and denominator slips, not hard ideas. Fix these early and your marks stay safe.

• Dropping the minus sign when a debt or negative number is added.
• Forgetting to take a common denominator before adding fractions.
• Calling a decimal terminating without checking the denominator's prime factors.

Sample Solved Question from Class 9 Maths Chapter 3

Here is one Exercise 3.4 type question, solved step by step, so you can see the method.

Question: Find three distinct rational numbers that lie strictly between -12 and 14.

Step 1. Rewrite both numbers with the same denominator. Using 8, you get -12 = -48 and 14 = 28.

Step 2. Look for eighths whose top lies between -4 and 2. Any n8 with -4 < n < 2 works.

Step 3. Pick three, say n = -2, 0, 1. These give -14, 0, and 18.

Final answer. Three such numbers are -14, 0, and 18. Many other answers are also correct.

How to Study The World of Numbers and Time Needed

This chapter builds in a clear order, so do not skip ahead. Start with the integer sets, then rational numbers, then decimals. Use the NCERT Solutions Class 9 Maths Chapter 3 The World of Numbers to check each End-of-Chapter answer.

How will Collegedunia's NCERT Solutions Help You with The World of Numbers?

Collegedunia gives you the full NCERT Solutions Class 9 Maths Chapter 3 The World of Numbers as clean, step-by-step answers in one place.

• 2026-27 Ganita Manjari match: Every answer follows the new book, not the old chapter list.
• Full working shown: Each sign, denominator, and decimal step is written out.
• Teacher checked: Subject experts verify each sum and each decimal expansion.
• Free PDF: Download the solutions from Collegedunia and revise offline before your exam.

More The World of Numbers Maths Class 9 Resources

NCERT Solutions for Class 9 Maths: All Chapters

Use the table below to open the NCERT Solutions for any other chapter of the new Class 9 Maths book.