Back To Course

Math 102: College Mathematics15 chapters | 122 lessons | 13 flashcard sets

Are you a student or a teacher?

Start Your Free Trial To Continue Watching

As a member, you'll also get unlimited access to over 75,000 lessons in math, English, science, history, and more. Plus, get practice tests, quizzes, and personalized coaching to help you succeed.

Free 5-day trial
Your next lesson will play in
10 seconds

Lesson Transcript

Instructor:
*Chad Sorrells*

Chad has taught Math for the last 9 years in Middle School. He has a M.S. in Instructional Technology and Elementary Education.

A permutation is a method used to calculate the total outcomes of a situation where order is important. In this lesson, John will use permutations to help him organize the cards in his poker hand and order a pizza.

John is an avid card player. His favorite card game to play is poker. The best part about playing poker for him is the moment when the cards are dealt. John has always been curious about how many different ways he could organize his cards. John seemed to remember that this was called a **permutation**. He researched and found that a permutation is an arrangement of items or events in which order is important. The next time he played poker, he wanted to calculate how many different ways he could organize his cards that he was dealt. The dealer dealt him an Ace of spades, 7 of clubs, 7 of diamonds, Jack of hearts and a 2 of clubs.

To calculate this permutation, John will need to use five blanks to represent the five cards that each player was dealt. John knew that he had five different cards to organize. So, for the first card, he could use any of the five cards. So, John had five choices for the first card. For each subsequent blank, John will have one less choice because he is using cards in the previous blanks. So, in the third blank he will have three choices; in the fourth blank, two choices; and in the fifth blank, one choice.

John now realizes that he has five choices for the first card, four options for the second card, three options for the third card, two options for the fourth card and one option for the fifth card. To find the number of ways that he can organize his cards, he now needs to multiply these numbers together. John multiplied 5 * 4 * 3 * 2 * 1, and the product was 120. John now knows that there are 120 ways to organize his poker hand of cards.

Another way to think about permutations is to understand **factorials**. A factorial is the product of all of the positive integers equal to and less than your number. A factorial is written as a number followed by an exclamation point. For example, to write the factorial of 5, you would write 5!. To calculate the factorial of 5, you would multiply all of the positive integers equal to and less than 5. 5! = 5 * 4 * 3 * 2 * 1. By multiplying these numbers together, we can find that 5! = 120.

Let's look at another example - how would we write and solve the factorial of 10? The factorial of 10 would be written as 10!. To calculate 10!, it would equal 10 * 9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1 = 3,628,800.

When writing permutations, we use the notation *n**P**r*, where *n* represents the number of items to choose from, P stands for permutation and *r* stands for how many items you are choosing. To calculate the permutation using this formula, you would use *n**P**r* = *n*! / (*n* - *r*)!.

John is still playing poker and enjoying a lot of success. The dealer asks the group of six players if four of them would like to join a private game. John is excited but curious about how many different ways the four players can be selected. Using the formula *n**P**r*, *n* would represent the total number of players, which is 6. The *r* term would represent the number of players that are being chosen, which is 4. So, this equation would look like 6*P*4.

To solve this equation, John will calculate 6! and divide it by (6 - 4)!. The first thing John must do is subtract the (6 - 4) in the denominator to get 2. John's equation now looks like 6! / 2!. To calculate 6!, John will multiply 6 * 5 * 4 * 3 * 2 * 1 = 720, and 2! = 2 * 1 = 2. So, we now have 720 / 2, which equals 360. There are 360 ways that four players from John's table can be selected to play at a private table.

Before heading to the private poker game, John stops by the snack bar. The snack bar makes pizzas and has a total of ten toppings. The snack bar sells pizzas with a maximum number of four toppings. How many different types of pizzas can John make?

To calculate the number of choices, you would need to use the equation 10*P*4 = 10! / (10 - 4)! The first step that John must do is subtract (10 - 4) = 6. So, 10! / (10 - 4)! = 10! / 6!. To calculate 10!, you would multiply 10 * 9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1. To calculate the 6!, you would multiply 6 * 5 * 4 * 3 * 2 * 1. The easiest way to calculate the total number of choices is to cancel out common terms. Since 6 * 5 * 4 * 3 * 2 * 1 appears on both the top and bottom, these terms can be cancelled out. So, this would leave (10 * 9 * 8 * 7 ) / 1, which equals 5,040 / 1, which equals 5,040. John can choose from 5,040 different types of pizza.

So, let's review what we've learned about permutations. A **permutation** is an arrangement of items or events in which order is important. Permutations help us find the total number of ways that items can be chosen when order does matter. A key tool in calculating permutations is factorials. **Factorials** are written with an exclamation point - for example, *n*!. To find the factorial of a number, multiply all of the positive integers equal to or less than that number. For example, 7! = 7 * 6 * 5 * 4 * 3 * 2 * 1 = 5,040.

To calculate permutations, we use the equation *n*P*r*, where *n* is the total number of choices and *r* is the amount of items being selected. To solve this equation, use the equation *n**P**r* = *n*! / (*n* - *r*)!.

Following this lesson, you'll be able to:

- Express the characteristics of a permutation and a factorial
- Write the equation for calculating permutations
- Solve permutation problems

To unlock this lesson you must be a Study.com Member.

Create your account

Are you a student or a teacher?

Already a member? Log In

BackDid you know… We have over 160 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

You are viewing lesson
Lesson
12 in chapter 13 of the course:

Back To Course

Math 102: College Mathematics15 chapters | 122 lessons | 13 flashcard sets

- Go to Logic

- Go to Sets

- Understanding Bar Graphs and Pie Charts 9:36
- How to Calculate Percent Increase with Relative & Cumulative Frequency Tables 5:47
- How to Calculate Mean, Median, Mode & Range 8:30
- Calculating the Standard Deviation 13:05
- Probability of Simple, Compound and Complementary Events 6:55
- Probability of Independent and Dependent Events 12:06
- Either/Or Probability: Overlapping and Non-Overlapping Events 7:05
- Probability of Independent Events: The 'At Least One' Rule 5:27
- How to Calculate Simple Conditional Probabilities 5:10
- Math Combinations: Formula and Example Problems 7:14
- How to Calculate the Probability of Combinations 11:00
- How to Calculate a Permutation 6:58
- Go to Probability and Statistics

- Go to Geometry

- GRE Information Guide
- Computer Science 310: Current Trends in Computer Science & IT
- Earth Science 105: Introduction to Oceanography
- Computer Science 331: Cybersecurity Risk Analysis Management
- Computer Science 336: Network Forensics
- Practical Applications for Excel
- Practical Applications in Business Law
- Practical Applications for How to Network
- Practical Application for Technical Writing
- Practical Applications for Workplace Communications with Computers
- MEGA Test Accomodations
- Study.com Grant for Teachers
- What are the MEGA Tests?
- MOGEA Test Score Information
- ASWB Prep Product Comparison
- What is the MOGEA Test?
- TASC Exam Registration Information

- Promoting Motor Learning With Activities, Sports & Games
- How to Teach Conflict Resolution to Kids
- Witchcraft in the Jacobean Era
- Best Practices for Teaching Gifted Students
- Practical Application: Principles of Composition in Graphic Design Infographic
- Recursion & Recursive Algorithms in Python: Definition & Examples
- Practical Application: Five Major Consumer Rights Infographic
- Food & Beverage Service & Operations: Assignment 2 - Research Paper
- Quiz & Worksheet - Aristotelian Virtue Ethics
- Quiz & Worksheet - Assessing Diverse Learners
- Quiz & Worksheet - Citizen Journalism Overview
- Quiz & Worksheet - Neolithic Period Overview
- Quiz & Worksheet - When to Intercede in Conflict as a Manager
- Flashcards - Measurement & Experimental Design
- Flashcards - Stars & Celestial Bodies

- UExcel Principles of Management: Study Guide & Test Prep
- College World History Textbook
- Praxis Special Education (5354): Practice & Study Guide
- Business Writing: Help & Review
- Team Building & Group Problem Solving
- Praxis Chemistry: Thermodynamics
- Moral Issues in Peacetime & War
- Quiz & Worksheet - Biological Treatments for Psychological Abnormalities
- Quiz & Worksheet - Quid Pro Quo vs. Hostile Environment Harassment
- Quiz & Worksheet - The Evolution of Prokaryotes
- Quiz & Worksheet - Cell Division Processes
- Quiz & Worksheet - Principles of Human Growth and Development

- Abnormal Human Development: Definition & Examples
- What Is a Current Account? - Definition & Examples
- Homeschooling in Wisconsin
- Florida State Standards for Language Arts
- How to Pass Actuarial Exams
- Best Free Online English Courses
- High School Summer Reading List
- Homeschooling in Kansas
- How to Become a National Board Certified Teacher
- How to Use Study.com in the Classroom
- South Dakota State Standards for Social Studies
- Science Writing Prompts

- Tech and Engineering - Videos
- Tech and Engineering - Quizzes
- Tech and Engineering - Questions & Answers

Browse by subject