Class 6 Maths Chapter 3, Number Play, explores creative number thinking—supercells in grids, number-line estimation, digit sums, palindromic numbers, D.R. Kaprekar’s magic constant 6174, clock/calendar patterns, the unsolved Collatz conjecture, estimation and winning game strategies.
What Class 6 Mathematics Chapter 3 Covers
3.1–3.6 Supercells, Number Lines, Palindromes & Kaprekar’s Constant interprets numbers as information (3.1), solves 1D and 2D Supercell grids where a cell exceeds all its adjacent neighbours (3.2), places multi-digit numbers on number lines (3.3), investigates digit sums and smallest/largest n-digit numbers (3.4), generates palindromes by reverse-and-add (3.5), and discovers Kaprekar’s constant 6174 for 4-digit numbers (3.6).
3.7–3.12 Clock/Calendar Numbers, Mental Math, Collatz Conjecture & Games explores palindromic clock times and 4×4 calendar grids (3.7), multi-digit mental addition/subtraction near 15,000 and 40,000 (3.8–3.9), the Collatz Conjecture (3n + 1 if odd, n/2 if even → 1) (3.10), Fermi estimation (3.11), and backward-reasoning winning strategies in number games (3.12).
Exercises in Chapter 3
- Figure it Out exercise sets across every section with step-by-step Chapter Solutions included at the end of the PDF.
- Summary key formulas, visual proofs, and mathematical puzzles.
Read Class 6 Mathematics Chapter 3 Online
More Chapters
- Previous: Chapter 2: Lines and Angles
- Next: Chapter 4: Data Handling and Presentation
- Hindi medium: Class 6 Maths Chapter 3 PDF in Hindi (Ganita Prakash)
- All Mathematics chapters and the other Class 6 books: Class 6 NCERT books 2026-27
- All Class 1 to 12 NCERT Textbooks: NCERT Books PDF (Class 1–12)
FAQ
What is Kaprekar’s constant and how is it reached?
6174 is Kaprekar’s constant. Take any 4-digit number with at least two different digits, arrange its digits in descending and ascending order to form the largest (A) and smallest (B) numbers, and subtract B from A; repeating this process always reaches 6174 in at most 7 steps.
What is the rule of the Collatz Conjecture?
Start with any positive whole number: if it is even, divide it by 2; if it is odd, multiply it by 3 and add 1. Repeating this rule is conjectured to always eventually reach the number 1.