Unit 2 Number Theory

Why Number Theory?
Number Theory deals with properties and relationships between numbers. 

Understanding how numbers relate to one another will give you tools that you can use that will make working with fractions much easier. 

To start, there are several words that you will need to be familiar with.  You don't need to learn them all at once, but pay attention to when and how they are used. 

Here are a few to get you started...

Factor - Sometimes it is easier to understand the meaning of a term by looking at an example. 
1, 2, 3 and 6 are factors of 6 because they are the whole numbers that can divide into 6 without leaving a remainder.  The factors of 5 are 1 and 5.  1 is a factor of every number.
A factor is a whole number that will divide into a given number without leaving a remainder.

Divisible - Six is divisible by 2 because 2 will divide into 6 without leaving a remainder.  Six is divisible by 1, 2, 3 and 6. 
A number is divisible by a number if it can be divided by that number without leaving a remainder.

Multiple - Six is a multiple of 2 because six can be obtained by multiplying 2 times an integer (not a fraction).  The multiples of 3 are 3, 6, 9, 12, 15, etc. 
A multiple is the result of multiplying a number by an integer. 

This unit has 5 sections.  Work through each section in order, making certain you are feeling proficient with each section before moving on.  These concepts and skills are the key building blocks we will be using when we work with fractions.  The more fluent you are with these skills, the smoother your work with fractions will be.

Multiplication Rectangles 
Divisibility Rules And The Sieve Of Eratosthenes 
Listing Factors 
Prime Factorization 
Multiples And LCM