Class 6 Math: Playing with Numbers Quick Revision Chapter Summary

Need to review the entire chapter before a test? This quick revision guide summarizes all the core concepts, topics, and equations taught in Class 6 Playing with Numbers to help you refresh your memory instantly.

Core Topics At a Glance

### 📌 Factors and Multiples A factor divides a number completely without leaving a remainder. A multiple is the product of that number and an integer.

### 📌 Prime and Composite numbers Prime numbers have exactly two factors: 1 and the number itself. Composite numbers have more than two factors.

### 📌 Tests for divisibility (2, 3, 4, 5, 6, 8, 9, 10, 11) Divisibility tests check if a number divides another evenly using quick digit rules.

### 📌 Common factors and Common multiples Common factors divide two or more numbers. Common multiples are divisible by two or more numbers.

### 📌 HCF and LCM algorithms Prime factorization and common division methods used to find the Highest Common Factor (HCF) and Least Common Multiple (LCM) of numbers.

Key Formulas Mind Map

• Divisibility by 3 Rule: `\sum \text{digits} = 3k` - A number is divisible by 3 if the sum of its digits is a multiple of 3....

Revision Checklist

1. Review the subtopic guides and outline notes.
2. Practice writing the key formulas from memory.
3. Solve at least 3 worked examples and check your steps.
4. Take a timed practice quiz to verify your speed.