Exercise 3.9

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NCERT Solutions for Class 8 Maths Chapter 3 A Story of Numbers - Exercise 3.9

Mastering rapid calculations is simple with our NCERT Solutions for Class 8 Maths Ch 3: A Story of Numbers – Exercise 3.9. This exercise moves beyond the traditional long multiplication method. You will learn how to square numbers ending in 5 in seconds, use the "Base Method" for numbers near 100, and apply the "Duplex Method" for general squaring.

Class 8 Math Lessons (Ch 3): Learn to Square Numbers Mentally with Ease! The solutions to Exercise 3.9 of Class 8 Maths will be presented in a step-by-step approach to give students a clear understanding of the shortcuts that make competitive exams easier. The solutions are in accordance with the CBSE Guidelines to improve numerical fluency. Additionally, these solutions will aid students in checking their own answers during exams without having to re-calculate the entire problem.

1.0Download Class 8 Maths Chapter 3 Ex 3.9 NCERT Solutions PDF

Our easy-to-follow NCERT Solutions for Class 8 Maths Chapter 3 Exercise 3.9 are available for download as a PDF. Perfect for offline study and quick reference before exams.

NCERT Solutions Class 8 Maths Chapter 3 Ex 3.9

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2.0Key Concepts of Chapter 3 Exercise 3.9

Squaring Numbers ending in 5: A shortcut where you multiply the digits before the 5 by their successor and append "25" to the end.
Base Method (Near 100): Finding the square of numbers like 98 or 104 by calculating their deviation from 100.
The Identity Method: Using $(a + b)^{2} = a^{2} + 2 ab + b^{2}$ to break down two-digit squares into mental calculation steps.
Digital Roots: A technique to verify if a number is a perfect square by summing its digits until a single digit remains.

3.0NCERT Solutions for Class 8 Maths Chapter 3 A Story of Numbers : All Exercises

NCERT Solutions for Class 8 Maths Chapter 3 A Story of Numbers - Exercise 3.1

NCERT Solutions for Class 8 Maths Chapter 3 A Story of Numbers - Exercise 3.2

NCERT Solutions for Class 8 Maths Chapter 3 A Story of Numbers - Exercise 3.3

NCERT Solutions for Class 8 Maths Chapter 3 A Story of Numbers - Exercise 3.4

NCERT Solutions for Class 8 Maths Chapter 3 A Story of Numbers - Exercise 3.5

NCERT Solutions for Class 8 Maths Chapter 3 A Story of Numbers - Exercise 3.6

NCERT Solutions for Class 8 Maths Chapter 3 A Story of Numbers - Exercise 3.7

NCERT Solutions for Class 8 Maths Chapter 3 A Story of Numbers - Exercise 3.8

NCERT Solutions for Class 8 Maths Chapter 3 A Story of Numbers - Exercise 3.9

4.0Benefits of NCERT Solutions for Class 8 Maths Chapter 3 Exercise 3.9

Conceptual Clarity: Explains the "why" behind mathematical shortcuts.
Exam-Oriented: Vital for time-management in multiple-choice exams like Olympiads or NTSE.
Logical Steps: Provides a clear breakdown of Vedic math techniques into standard algebraic steps.
Error Prevention: Teaches students how to use digital roots to spot a wrong answer in seconds.

NCERT Class 8 Maths Ch. 3 A Story of Numbers Other Exercises:-

Exercise 3.9

NCERT Solutions Class 8 Maths All Chapters:-

Chapter 1 - A Square and a Cube

Chapter 2 - Power play

Chapter 3 - A story of Numbers

Chapter 4 - Quadrilaterals

Chapter 5 - Number Play

Chapter 6 - We distibute, yet thinmgs multiply

Chapter 7 - Proportional Reasoning