Class 8 · Chapter 3
A Story of Numbers
Rational numbers: representation, operations, properties.
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Ganita Prakash · Class 8 Part 1 (2026-27)
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Tip: NCERT updated the syllabus for 2026-27. The links above open the latest edition on the official portal — chapter titles and numbering may differ from the notes shown here.
Detailed theory
Add/subtract via common denominator. Multiply straight. Divide by multiplying by reciprocal. Simplify final answer.
Key concepts & formulas
01
**Rational**: where integers, .
02
Closed under (except ).
03
Additive inverse of : .
04
Multiplicative inverse (reciprocal) of : .
05
Between any two rationals, infinitely many rationals lie.