CBSE · Class 6-12

Class 8 · Ganita Prakash

Unit 3 · Class 8Ganita Prakash

A Story of Numbers

Rational numbers: representation, operations, properties.

Lessons

3 concepts

1
Operations on Rationals
Add/subtract via common denominator. Multiply straight. Divide by multiplying by reciprocal. Simplify final answer.
2
Properties
Commutative & associative for $+$ and $\times$ . Distributive: $a(b+c) = ab+ac$ . Zero is additive identity; one is multiplicative identity.
3
Density of Rationals
Between $\tfrac 12$ and $\tfrac 34$ , we have $\tfrac 58$ , $\tfrac 9{16}$ , and infinitely many more.

Skills to practise

Skill · medium

A Story of Numbers — Practice