Study Notes
The Highest Common Factor (HCF) is the greatest number that divides two or more numbers without leaving a remainder. It can be found using the prime factorization or division method. Example: The HCF of 24 and 60 is 12. The Lowest Common Multiple (LCM) is the smallest positive integer that is divisible by two or more numbers. Example: The LCM of 6 and 10 is 30.
Exam Tips
Key Definitions to Remember
- The HCF is the largest number that divides two or more numbers without a remainder.
- The LCM is the smallest number that is a multiple of two or more numbers.
Common Confusions
- Confusing HCF with LCM; remember HCF is about division, LCM is about multiplication.
- Forgetting to use the lowest power of common prime factors for HCF.
Typical Exam Questions
- What is the HCF of 12 and 16? Answer: 4
- What is the LCM of 12 and 60? Answer: 60
- Find the HCF of 24 and 60 using the division method. Answer: 12
What Examiners Usually Test
- Ability to find HCF using both prime factorization and division methods.
- Understanding of how to calculate LCM using multiples and prime factorization.