📚 Part 1: Understanding HCF and LCM

1. What does HCF stand for?

Highest Common Factor

High Common Form

Heavy Common Function

Half Common Factor

2. The LCM of two numbers is:

The largest number that divides both numbers

The smallest number that both numbers divide into

The sum of both numbers

The difference between both numbers

3. Which of these are factors of 12? (Select all that apply)

1

2

3

4

5

6

4. The first five multiples of 8 are:

8, _____, _____, _____, _____

🔢 Part 2: Finding HCF and LCM

5. Complete the factor tree for 24:

24 = _____ × _____

Prime factorisation: 24 = _____ × _____ × _____ × _____

6. Find the HCF of 18 and 24:

Factors of 18: _________________________

Factors of 24: _________________________

Common factors: _______________________

HCF = _____

7. Find the LCM of 6 and 8:

Multiples of 6: _________________________

Multiples of 8: _________________________

Common multiples: _____________________

LCM = _____

8. Use prime factorisation to find the HCF and LCM of 12 and 15:

12 = _____ × _____ × _____

15 = _____ × _____

HCF = _____ (common prime factors)

LCM = _____ (all prime factors)

🎯 Part 3: Real-World Applications

9. Sarah organises chairs in rows for the school chapel. She has 36 chairs and wants equal rows with no chairs left over. List three different ways she could arrange the chairs:

10. Two bells ring at different intervals. Bell A rings every 12 minutes, and Bell B rings every 18 minutes. If they both ring at 9:00 AM, when will they next ring together?

This requires finding the _____ of 12 and 18.

Calculation: _________________________

Answer: They will ring together again at _____

11. Explain in your own words when you would use HCF in real life and when you would use LCM: