These worksheets teach your students how to determine if a number is prime or composite.

Primes or prime numbers are whole number values that have but two factors which are itself and one. Any value that has factors beside one and itself is classified as a composite number. There are two integers that do not match either of these groupings and that is zero and one. Since all even numbers are divisible by two, every value that is even and greater than two is a composite number. Also, all numbers that end in five are divisible by five, so any value greater than five that ends in a five is a composite number as well. We use these classifications to understand the significance of a value. Prime numbers act as the building blocks for all other numbers because composites are just primes that are multiplied together. We share with students the three-steps we can take to check if an integer is prime or composite. We start by identifying the square root of the number, calculators are acceptable for this. Your next step is to determine all the primes of the integer (of the square root). The last step is to divide your original number by all of the primes that you just have identified.

This section really helps you classify integers quickly. These worksheets explain how to determine whether or not a number is prime or composite and how to find the prime numbers within a given range of numbers.



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Print Prime or Composite Worksheets

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Is a Number Prime Lesson

This worksheet explains how to check to see whether or not a number is prime. The step-by-step solution to a sample problem is presented.

Practice Worksheet

Students will practice finding all the prime numbers within a given range. There are instructions on how to tell if a number is prime or composite, a sample problem is solved, and two practice problems are provided.

Chart the Classification

Students will fill out a chart to show whether or not the given numbers are prime or composite. Ten problems are provided.

Working within a Given Range

Students will identify all the prime numbers within a given range. Ten problems are provided.

What Do You Know?

Eight numbers are provided. Students will complete a chart to demonstrate whether a number is prime or composite.

Check Your Skills

Students will find the prime numbers within a given range, according to the specified instructions. Space is provided to copy the correct answer when provided.