Topics
Number System
Number System(Consolidating the Sense of Numberness)
Number System (Including Estimation and Approximation)
Theme 1 : Numbers
Estimation
Numbers in Indian and International Systems (With Comparison)
Theme 2 : Ratio, Proportion and Arithmetic Problems
Ratio and Proportion
Numbers in India and International System (With Comparison)
Theme 3 : Algebra
Natural Numbers and Whole Numbers (Including Number Line and Patterns)
Algebra
Negative Numbers and Integers
Place Value
Theme 4 : Geometry
Geometry
Theme 5 : Mensuration
Mensuration
Natural Numbers and Whole Numbers (Including Patterns)
Sets
Data Handling
Negative Numbers and Integers
Theme 6 : Statistics
Fractions
Number Line
Decimal Fractions
Playing with Numbers (Including H.C.F. and L.C.M.)
HCF and LCM
Ratio and Proportion (Including Unitary Method)
Playing with Numbers
- Simplification of Brackets
- Finding Factors Using Rectangular Arrangements and Division
- Factors and Common Factors
- Multiples and Common Multiples
- Concept of Even and Odd Number
- Tests for Divisibility of Numbers
- Divisibility by 2
- Divisibility by 4
- Divisibility by 8
- Divisibility by 3
- Divisibility by 6
- Divisibility by 9
- Divisibility by 5
- Divisibility by 11
Percent (Percentage)
Sets
Idea of Speed, Distance and Time
Ratio
Proportion (Including Word Problems)
Fundamental Concepts (With operations on Algebraic Expressions)
Framing Algebraic Expressions (Including Substitution and Linear Equations)
Unitary Method
Fundamental Concepts (Including Angles and their Properties)
Fractions
- Concept of Fraction
- Types of Fractions
- Concept of Proper and Improper Fractions
- Concept of Mixed Fractions
- Like and Unlike Fraction
- Concept of Equivalent Fractions
- Conversion between Improper and Mixed fraction
- Conversion between Unlike and Like Fractions
- Simplest Form of a Fractions
- Comparing Fractions
- Addition of Fraction
- Subtraction of Fraction
- Multiplication of Fraction
- Division of Fractions
- Using Operator 'Of' with Multiplication and Division
- BODMAS Rule
- Problems Based on Fraction
Triangles (Including Types and Properties of Triangles)
Decimal Fractions
Percent (Percentage)
Quadrilaterals
Circles
Idea of Speed, Distance and Time
Constructions
Symmetry
Fundamental Concepts
Fundamental Operations (Related to Algebraic Expressions)
Recognition of Solids
Substitution (Including Use of Brackets as Grouping Symbols)
Framing Algebraic Expressions (Including Evaluation)
Perimeter and Area of Plane Figures
Simple (Linear) Equations (Including Word Problems)
Data Handling (Including Mean and Median)
Fundamental Concepts
Angles (With Their Types)
Properties of Angles and Lines (Including Parallel Lines)
Triangles (Including Types, Properties and Constructions)
Quadrilateral
Polygons
The Circle
Symmetry (Including Constructions on Symmetry)
Recognition of Solids
Perimeter and Area of Plane Figures
Data Handling (Including Pictograph and Bar Graph)
Mean and Median
- Historical Note
- Step-by-Step Guide to Eratosthenes’ Prime Number Method
- Key Points Summary
Historical Note
Eratosthenes was an ancient Greek mathematician. He invented a simple, clever way to find all prime numbers up to any limit, known as the Sieve of Eratosthenes.
Step-by-Step Guide to Eratosthenes’ Prime Number Method

Step 1: Leave 1 as it is neither prime nor composite
Step 2: Encircle 2, cross out all the multiples of 2, other than 2 itself, i.e. 4, 6, 8, and so on.
Step 3: You will find that the next uncrossed number is 3. Encircle 3 and cross out all the multiples of 3, apart from 3 itself.
Step 4: The next uncrossed number is 5. Encircle 5 and cross out all the multiples of 5 other than 5 itself.
Step 5: Continue this process till all the numbers in the list are either encircled or crossed out. All the encircled numbers are prime numbers. All the crossed-out numbers, other than 1, are composite numbers. The total number of primes up to 100 is 25.
This method is called the Sieve of Eratosthenes.
Key Points Summary
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A prime number has exactly two factors: 1 and itself.
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The Sieve of Eratosthenes helps us find all primes up to a certain number.
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1 is not a prime number.
