Prime and Composite Numbers

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What are prime numbers?

Prime numbers are numbers greater than 1 that have only two factors: 1 and themselves.

What are composite numbers?

Composite numbers are numbers that have more than two factors.

Is 2 a prime or composite number?

2 is a prime number because it has only two factors: 1 and 2.

Is 4 a prime or composite number?

4 is a composite number because it has three factors: 1, 2, and 4.

Why is the number 1 neither prime nor composite?

1 is neither prime nor composite because it has only one factor: itself.

Is 5 a prime or composite number?

5 is a prime number because it has only two factors: 1 and 5.

Is 9 a prime or composite number?

9 is a composite number because it has three factors: 1, 3, and 9.

Can a prime number be even? If yes, which one?

Yes, the only even prime number is 2, because it is only divisible by 1 and itself.

List the prime numbers between 1 and 10.

The prime numbers between 1 and 10 are 2, 3, 5, and 7.

What is the smallest composite number?

The smallest composite number is 4.

How do you determine if a number is composite?

A number is composite if it can be divided evenly by numbers other than 1 and itself.

Is the number 11 a prime or composite number?

11 is a prime number because it has only two factors: 1 and 11.

What is a factor?

A factor is a number that divides evenly into another number.

Are all odd numbers prime? Why or why not?

No, not all odd numbers are prime, as some odd numbers can have more than two factors, like 9.

How can you test if a number is prime?

To test if a number is prime, check if it is divisible only by 1 and itself without leaving a remainder.





Test Your Knowledge

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1. What are prime numbers?

Prime numbers are numbers greater than 1 that have only two factors: 1 and themselves.

Prime numbers are numbers divisible by 1, itself, and 2.

Prime numbers are even numbers greater than 2.

Prime numbers are numbers greater than 1 that have more than two factors.

2. What are composite numbers?

Composite numbers are numbers that have only two factors: 1 and themselves.

Composite numbers are numbers that have only one factor.

Composite numbers are prime numbers greater than 10.

Composite numbers are numbers that have more than two factors.

3. Is 2 a prime or composite number?

2 is a prime number because it has only two factors: 1 and 2.

2 is a composite number because it has three factors.

2 is neither prime nor composite.

2 is a prime number because it is only divisible by 1 and 0.

4. Is 4 a prime or composite number?

4 is a composite number because it has three factors: 1, 2, and 4.

4 is a prime number because it has only two factors.

4 is neither a prime nor a composite number.

4 is a composite number because it has four factors: 1, 2, 3, and 4.

5. Why is the number 1 neither prime nor composite?

1 is neither prime nor composite because it has two factors: 1 and 2.

1 is neither prime nor composite because it has only one factor: itself.

1 is a prime number because it divides evenly into every number.

1 is neither prime nor composite because it can be divided by every number.

6. Is 5 a prime or composite number?

5 is a prime number because it has only two factors: 1 and 5.

5 is a composite number because it is divisible by 2.

5 is neither prime nor composite.

5 is a composite number as it has three factors: 1, 5, and itself.

7. Is 9 a prime or composite number?

9 is a composite number because it has three factors: 1, 3, and 9.

9 is a prime number because it has only itself and 1 as factors.

9 is a prime number because it is odd.

9 is neither prime nor composite.

8. Can a prime number be even? If yes, which one?

Yes, the only even prime number is 2, because it is only divisible by 1 and itself.

No, all prime numbers are odd.

Yes, 4 is the only even prime number.

No, since all even numbers are composite.

9. List the prime numbers between 1 and 10.

2, 4, 6, and 8.

2, 3, 5, and 7.

1, 3, 5, and 9.

2, 3, 4, and 9.

10. What is the smallest composite number?

The smallest composite number is 4.

The smallest composite number is 2.

The smallest composite number is 3.

The smallest composite number is 5.

11. How do you determine if a number is composite?

A number is composite if it can be divided evenly by numbers other than 1 and itself.

A number is composite if it can only be divided by 1 and itself.

A number is composite if it is greater than 10.

A number is composite if it is an even number.

12. Is the number 11 a prime or composite number?

11 is a composite number because it has three factors.

11 is a prime number because it has only two factors: 1 and 11.

11 is neither prime nor composite.

11 is a composite number because it is odd.

13. What is a factor?

A factor is a prime number that has no other factors.

A factor is a number that divides evenly into another number.

A factor is any number that can divide 10.

A factor is an even number.

14. Are all odd numbers prime? Why or why not?

Yes, because odd numbers are not divisible by 2.

No, not all odd numbers are prime, as some odd numbers can have more than two factors, like 9.

Yes, because all primes are odd.

No, because odd numbers are always composite.

15. How can you test if a number is prime?

To test if a number is prime, check if it is divisible only by 1 and itself without leaving a remainder.

To test if a number is prime, check if it is an even number.

To test if a number is prime, ensure it is odd and greater than 1.

To test if a number is prime, use divisibility rules for 5 and 10.