# Ch 4: 8th Grade Math: Number Theory

### About This Chapter

## Number Theory - Chapter Summary

The video lessons in the Number Theory chapter could assist you in teaching the students in your 8th grade class how to find prime factorization with exponents or the least common multiple. There is a chapter exam at the end for further assessment of students' comprehension of number theory.

## Chapter Lessons and Objectives

Lesson | Objective |
---|---|

Converting Numbers to Scientific Notation | Students learn how to write very large and small numbers using scientific notation, and how to convert to scientific notation. |

Comparing Numbers Written in Scientific Notation | In this lesson, students learn how to compare numbers that are expressed with scientific notation. |

Identifying Prime and Composite Numbers | This lesson teaches students how to differentiate between prime and composite numbers. |

How to Find the Prime Factorization of a Number | In this lesson, techniques for finding the prime factorization of numbers are presented. |

Finding the Prime Factorization with Exponents | Students are taught how to factor numbers with prime numbers and exponents. |

How to Find the Greatest Common Factor | The instructor defines what a factor is and teaches students how to determine the greatest common factor. |

How to Find the Least Common Multiple | This lesson covers how the least common multiple can be found. |

Using Prime Factorizations to Find the Least Common Multiples | The process of finding least common multiples with prime factorizations is explored in this lesson. |

Word Problems: Greatest Common Factor & Least Common Multiple | In this lesson, students learn techniques for understanding and completing greatest common factor and least common multiple word problems. |

### 1. Converting Numbers to Scientific Notation

After watching this video lesson, you will be able to convert any number you come across into scientific notation. You will also learn why scientific notation is used and where you are most likely to see it.

### 2. Comparing Numbers Written in Scientific Notation

After watching this video lesson, you will be able to compare numbers written in scientific notation with each other. You will learn how to tell which is larger and which is smaller.

### 3. Identifying Prime & Composite Numbers

In this video lesson, you will learn how to identify both prime and composite numbers. You will also learn what makes the numbers unique, as well as the characteristics of both these types of numbers.

### 4. How to Find the Prime Factorization of a Number

The prime factorization of a number involves breaking that number down to its smallest parts. This lesson will show you two different ways to discover the prime factorization of any number.

### 5. Finding the Prime Factorization with Exponents

After watching this video lesson, you will be able to factor any number using just prime numbers and exponents. Learn how to break apart any number you are given. Then, test your new knowledge with some examples.

### 6. How to Find the Greatest Common Factor

If the factors of a number are the different numbers that you can multiply together to get that original number, then the greatest common factor of two numbers is just the biggest one that both have in common. See some examples of what I'm talking about here!

### 7. How to Find the Least Common Multiple

The least common multiple of two numbers is the smallest number that can be divided evenly by your two original numbers. See some examples of what I'm talking about here!

### 8. Using Prime Factorizations to Find the Least Common Multiples

Finding the least common multiple can seem like a lot of work. But we can use prime factorization as a shortcut. Find out how and practice finding least common multiples in this lesson.

### 9. Word Problems: Greatest Common Factor & Least Common Multiple

In this video lesson, you will learn what kinds of word problems you can expect to see that involve the greatest common factor or the least common multiple. Learn what you need to do to understand these problems and then to solve them.

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### Other Chapters

Other chapters within the 8th Grade Math: Practice & Review course

- 8th Grade Math: Basic Arithmetic Operations
- 8th Grade Math: Divisibility
- 8th Grade Math: Number Properties
- 8th Grade Math: Factoring
- 8th Grade Math: Estimation and Rounding
- 8th Grade Math: Whole Numbers
- 8th Grade Math: Simplifying Whole Number Expressions
- 8th Grade Math: Negative Numbers
- 8th Grade Math: Absolute Value
- 8th Grade Math: Integers
- 8th Grade Math: Rational Numbers
- 8th Grade Math: Inequalities
- 8th Grade Math: Introduction to Decimals
- 8th Grade Math: Operations with Decimals
- 8th Grade Math: Introduction to Fractions
- 8th Grade Math: Operations with Fractions
- 8th Grade Math: Percents
- 8th Grade Math: Exponents & Exponential Expressions
- 8th Grade Math: Roots & Radical Expressions
- 8th Grade Math: Basic Algebraic Expressions
- 8th Grade Math: Algebraic Distribution
- 8th Grade Math: Simplifying & Solving Rational Expressions
- 8th Grade Math: The Coordinate Graph
- 8th Grade Math: Linear Equations
- 8th Grade Math: Systems of Linear Equations
- 8th Grade Math: Properties of Functions
- 8th Grade Math: Graphing Functions
- 8th Grade Math: Solving Math Word Problems
- 8th Grade Math: Introduction to Geometric Figures
- 8th Grade Math: Triangles in Geometry
- 8th Grade Math: Quadrilaterals in Geometry
- 8th Grade Math: Circles in Geometry
- 8th Grade Math: Circular Arcs & Measurement in Geometry
- 8th Grade Math: Polyhedrons and Geometric Solids
- 8th Grade Math: Symmetry, Similarity & Congruence in Geometry
- 8th Grade Math: Triangle Theorems and Proofs in Geometry
- 8th Grade Math: Similar Polygons in Geometry
- 8th Grade Math: The Pythagorean Theorem in Geometry
- 8th Grade Math: Units of Measurement
- 8th Grade Math: Measuring Perimeter & Area
- 8th Grade Math: Data & Graphs
- 8th Grade Math: Probability
- 8th Grade Math: Statistics
- 8th Grade Math: Rates, Ratios & Proportions
- 8th Grade Math: Consumer Math
- 8th Grade Math: Number Sequences
- 8th Grade Math: Sets & Subsets
- 8th Grade Math: Algebraic Monomials & Polynomials