Study Notes
Factors and multiples are fundamental concepts in mathematics that help in understanding numbers and their relationships.
- Multiples — numbers that a given number can divide into without leaving a remainder. Example: The multiples of 3 are 3, 6, 9, 12, 15...
- Common Multiples — numbers that are multiples of two or more numbers. Example: 40 is a common multiple of 4 and 5.
- Lowest Common Multiple (LCM) — the smallest number that is a multiple of two or more numbers. Example: The LCM of 4 and 5 is 20.
- Factors — numbers that divide exactly into another number. Example: The factors of 8 are 1, 2, 4, 8.
- Common Factors — numbers that are factors of two or more numbers. Example: 2, 5, and 10 are common factors of 30 and 20.
- Highest Common Factor (HCF) — the greatest factor that divides two or more numbers. Example: The HCF of 30 and 36 is 6.
Exam Tips
Key Definitions to Remember
- Multiples are numbers that a given number can divide into without a remainder.
- Common multiples are numbers that are multiples of two or more numbers.
- The lowest common multiple (LCM) is the smallest common multiple of two or more numbers.
- Factors are numbers that divide exactly into another number.
- Common factors are numbers that are factors of two or more numbers.
- The highest common factor (HCF) is the greatest factor that divides two or more numbers.
Common Confusions
- Confusing factors with multiples.
- Mixing up LCM and HCF.
Typical Exam Questions
- What are the multiples of 4? 4, 8, 12, 16, 20...
- Find the LCM of 3 and 6? 6
- What is the HCF of 30 and 36? 6
What Examiners Usually Test
- Ability to list factors and multiples.
- Finding common multiples and factors.
- Calculating LCM and HCF using different methods.