Grade 4 · Math · Lesson 6

Learn Prime and Composite Numbers

Every whole number greater than 1 is either prime or composite. Understanding how numbers divide helps us work with factors, fractions, and algebra.

What this lesson teaches

1Define a prime number as a number with exactly two factors: 1 and itself
2Define a composite number as a number with more than two factors
3Identify prime and composite numbers up to 50
4List the prime numbers from 1 to 20

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