# Prime and Composite Numbers Worksheets

### About These 15 Worksheets

Prime and composite numbers worksheets play a crucial role in helping students internalize the concept of prime and composite numbers, develop their problem-solving skills, and build a foundation for future mathematical learning.

As students solve numerous problems, they begin to notice patterns and relationships among prime and composite numbers. This encourages them to explore deeper mathematical concepts and discover unique properties of these numbers.

Prime and composite numbers are fundamental concepts in number theory, which is the study of the properties and relationships of numbers. Understanding these concepts provides a solid foundation for higher-level mathematics.

These worksheets come in handy when we are working on basic algebra skills because prime numbers have only two distinct factors: 1 and themselves. Composite numbers, on the other hand, have more than two factors. Being able to differentiate between the two helps students understand the concept of factors and how numbers can be broken down into smaller building blocks.

### What are Prime Numbers?

Imagine you have a box of colorful building blocks. Some of these blocks can only be made by stacking one block on top of another, while others can be made in different ways, like by arranging blocks in rows and columns. In the world of numbers, prime numbers are like those blocks that can only be stacked one on top of the other.

A prime number is a special number greater than 1 that can only be divided by 1 and itself without leaving any leftover pieces. For example, 2, 3, 5, and 7 are prime numbers. You can’t divide them by any other number and get a whole number answer.

### What are Composite Numbers?

Now, composite numbers are the opposite of prime numbers. They are like blocks that can be arranged in different ways, not just stacked up. Composite numbers are those that can be divided by numbers other than just 1 and themselves.

For example, the number 4 is a composite number. You can divide it by 1, 2, and 4. Another example is 6; you can divide it by 1, 2, 3, and 6.

### Types of Exercises on the Worksheets

**Circle the Prime Numbers** – In this type of exercise, you’ll see a list of numbers. Your task is to circle or color all the prime numbers.

Example: Numbers – 2, 4, 5, 6, 9

You would circle – 2 and 5 because they’re prime!

**Underline the Composite Numbers** – Just like the previous exercise, but this time, you underline or highlight the composite numbers.

Example: Numbers – 3, 7, 8, 10, 11

You would underline – 8 and 10.

**Matching Pairs** – This exercise will have two columns. One with numbers and another with the words ‘prime’ and ‘composite’. You draw a line connecting each number to the right word.

Example: Column A – 2, 9, 12, Column B – Prime, Composite

You would connect 2 to ‘Prime’, 9 and 12 to ‘Composite’.

**Factoring Fun**– In this game, you’ll list all the numbers that can multiply together to give the number in question. This helps to see if a number is prime or composite.

Example: Number – 6

Factors – 1, 2, 3, 6

**Color the Grid** – You’ll get a grid filled with numbers. Using different colors, you color in the prime numbers with one color and the composite numbers with another.

**Fill in the Blanks** – This exercise has sentences with blanks. Fill them in using the correct number type (prime or composite).

Example: 10 is a ________ number.

Answer – Composite