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# Prime factorization

4 videos
3 skills
You know what prime numbers are and how to identify them. In this tutorial, we'll see that *all* positive whole numbers can be broken down into products of prime numbers (In some way, prime numbers are the "atoms" of the number world that can be multiplied to create any other number). Besides being a fascinating idea, it is also extremely useful. Prime factorization can be used to decrypt encrypted information!

### Prime factorization

VIDEO 4:09 minutes
Prime Factorization

### Prime factorization exercise

VIDEO 3:49 minutes

### Prime factorization

PRACTICE PROBLEMS

### The fundamental theorem of arithmetic

VIDEO 4:33 minutes
Ben Eater and Sal walk through the "Fundamental theorem of arithmetic" module: http://www.khanacademy.org/math/arithmetic/factors-multiples/e/the_fundamental_theorem_of_arithmetic

### The fundamental theorem of arithmetic

PRACTICE PROBLEMS

### Common divisibility examples

VIDEO 7:55 minutes
Common Divisibility Examples

### Divisibility

PRACTICE PROBLEMS