🏗️ What is a Composite Number?
A **composite number** is a whole number greater than 1 that has **more than two factors**.
That means it can be divided evenly by numbers other than just 1 and itself.
🌟 Examples of Composite Numbers
Composite Numbers:
4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25...
Remember:
• Prime numbers have exactly 2 factors (1 and itself)
• Composite numbers have more than 2 factors
• 1 is neither prime nor composite
🔍 How to Tell if a Number is Composite
- The number must be greater than 1.
- Check if it has any factors besides 1 and itself.
- If yes → It is composite!
Example: Is 15 composite?
Factors of 15: 1, 3, 5, 15 → More than 2 factors → Yes, composite
✏️ Let’s Practice Together, My Dear Student!
Practice 1: Prime or Composite?
1. 9 → Composite (1, 3, 9)
2. 11 → Prime
3. 25 → Composite (1, 5, 25)
4. 29 → Prime
Practice 2: List the Factors
1. Factors of 16 → 1, 2, 4, 8, 16 (composite)
2. Factors of 19 → 1, 19 (prime)
Practice 3: Word Problems (Canadian Style)
1. A teacher wants to divide 24 students into equal teams. What are all the possible team sizes?
Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24 → 24 is composite
2. Which of these numbers is composite: 13, 17, 21, 23?
21 is composite (1, 3, 7, 21)
Challenge Question
Is 1 a composite number? Why or why not?
No — 1 has only one factor (itself). It is neither prime nor composite.
🔗 Prime vs Composite
All whole numbers greater than 1 are either **prime** or **composite**. They help us understand how numbers are built!
Fantastic Job, My Dear Student! 🎉
You now understand Composite Numbers very well! Most numbers we use every day are composite numbers.
I am so proud of you for learning all about primes and composites. You are becoming a real number expert!
💕 You are smart. You are kind. You can do hard things.
When you are ready, tell me the next topic and I will create another beautiful lesson just for you!