# Ch 4: 6th-8th Grade Math: Number Theory

### About This Chapter

## Number Theory - Chapter Summary

This Number Theory chapter focuses on improving your students' knowledge of terms such as scientific notation, the greatest common factor and the least common multiple. The video lessons in this chapter can help students learn how to complete word problems, identify composite numbers and determine the prime factorization of a number. The videos contain tags for easy navigation to key points, and you will find useful self-assessment quizzes with the lessons.

## Chapter Lessons and Objectives

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

Converting Numbers to Scientific Notation | In this lesson, students learn to convert numbers in standard notation to scientific notation. |

Comparing Numbers Written in Scientific Notation | Students learn to compare and order numbers in scientific notation. |

Identifying Prime and Composite Numbers | Instructors show students how to differentiate between composite numbers and prime numbers. |

How to Find the Prime Factorization of a Number | With this lesson, students can learn how to identify prime numbers and factors of numbers. |

Finding the Prime Factorization with Exponents | Students learn to determine when to use exponents when finding the prime factorization. |

How to Find the Greatest Common Factor | In this lesson, instructors teach the rules for calculating the greatest common factor. |

How to Find the Least Common Multiple | Instructors show their students how to determine the least common multiple. |

Using Prime Factorizations to Find the Least Common Multiples | Students discover the steps involved in using prime factorizations to find the least common multiple. |

Word Problems: Greatest Common Factor and Least Common Multiple | In this lesson, students learn to solve word problems that include the greatest common factor and the least common multiple. |

### 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 6th-8th Grade Math: Practice & Review course

- 6th-8th Grade Math: Basic Arithmetic Operations
- 6th-8th Grade Math: Divisibility
- 6th-8th Grade Math: Properties of Numbers
- 6th-8th Grade Math: Factoring
- 6th-8th Grade Math: Estimating & Rounding
- 6th-8th Grade Math: Whole Numbers
- 6th-8th Grade Math: Simplifying Whole Number Expressions
- 6th-8th Grade Math: Negative Numbers
- 6th-8th Grade Math: Absolute Value
- 6th-8th Grade Math: Integers
- 6th-8th Grade Math: Rational Numbers
- 6th-8th Grade Math: Inequalities
- 6th-8th Grade Math: Introduction to Decimals
- 6th-8th Grade Math: Operations with Decimals
- 6th-8th Grade Math: Introduction to Fractions
- 6th-8th Grade Math: Operations with Fractions
- 6th-8th Grade Math: Percents
- 6th-8th Grade Math: Exponents & Exponential Expressions
- 6th-8th Grade Math: Roots & Radical Expressions
- 6th-8th Grade Algebra: Writing Algebraic Expressions
- 6th-8th Grade Algebra: Basic Algebraic Expressions
- 6th-8th Grade Algebra: Algebraic Distribution
- 6th-8th Grade Algebra: Writing & Solving One-Step Equations
- 6th-8th Grade Algebra: Writing & Solving Two-Step Equations
- 6th-8th Grade Algebra: Simplifying & Solving Rational Expressions
- 6th-8th Grade Math: The Coordinate Graph
- 6th-8th Grade Algebra: Linear Equations
- 6th-8th Grade Algebra: Systems of Linear Equations
- 6th-8th Grade Math: Properties of Functions
- 6th-8th Grade Math: Graphing Functions
- 6th-8th Grade Math: Solving Math Word Problems
- 6th-8th Grade Measurement: Perimeter & Area
- 6th-8th Grade Geometry: Introduction to Geometric Figures
- 6th-8th Grade Geometry: Angles
- 6th-8th Grade Measurement: Units of Measurement
- 6th-8th Grade Geometry: Triangles
- 6th-8th Grade Geometry: Quadrilaterals
- 6th-8th Grade Geometry: Circles
- 6th-8th Grade Geometry: Circular Arcs & Measurement
- 6th-8th Grade Geometry: Polyhedrons & Geometric Solids
- 6th-8th Grade Geometry: Symmetry, Similarity & Congruence
- 6th-8th Grade Geometry: Transformations
- 6th-8th Grade Geometry: Triangle Theorems & Proofs
- 6th-8th Grade Geometry: Similar Polygons
- 6th-8th Grade Geometry: The Pythagorean Theorem
- 6th-8th Grade Math: Data & Graphs
- 6th-8th Grade Math: Probability
- 6th-8th Grade Math: Statistics
- 6th-8th Grade Math: Rates, Ratios & Proportions
- 6th-8th Grade Math: Money
- 6th-8th Grade Math: Consumer Math
- 6th-8th Grade Math: Number Sequences
- 6th-8th Grade Math: Sets
- 6th-8th Grade Algebra: Monomials & Polynomials