Prime Numbers
Prime numbers are whole numbers greater than 1 that have exactly two factors: 1 and themselves. In Grade 8 Saxon Math Course 3, students identify prime numbers, distinguish them from composite numbers, and use prime numbers in factorization and number theory applications. Understanding prime numbers is foundational for GCF, LCM, and algebraic reasoning.
Key Concepts
Prime numbers are counting numbers greater than 1 that have exactly two different counting number factors, the number itself and 1. What’s next.
This lesson is your starting point. Soon, we'll use worked examples with factor trees and divisibility tests to find the prime components of any number.
Common Questions
What is a prime number in 8th grade math?
A prime number is a whole number greater than 1 that has exactly two distinct factors: 1 and itself. Examples include 2, 3, 5, 7, 11, and 13.
How do you identify if a number is prime?
Check if the number has any factors other than 1 and itself. You only need to test divisibility by primes up to the square root of the number.
Is 1 a prime number?
No, 1 is not prime. Prime numbers must have exactly two distinct factors; 1 only has one factor (itself), so it is classified as neither prime nor composite.
What is the difference between prime and composite numbers?
A prime number has exactly two factors (1 and itself), while a composite number has more than two factors. For example, 7 is prime, but 6 is composite because it has factors 1, 2, 3, and 6.
Why are prime numbers important in Grade 8 math?
Prime numbers are used in prime factorization, finding GCF and LCM, simplifying fractions, and are the building blocks of all whole numbers greater than 1.