Back To Course

Algebra I: High School20 chapters | 168 lessons | 1 flashcard set

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:
*Jeff Calareso*

Jeff teaches high school English, math and other subjects. He has a master's degree in writing and literature.

Maybe you know that 95% is an A and 75% is a C. But what do those percents really mean? In this lesson, we'll learn about percents, including how to convert them to fractions and decimals.

OK, team, I need you to give all you've got. I want you to go out there and give 110%. I know it sounds impossible. And, well, it is. Before we work on plays, let's talk about percents.

The word **percent** literally means 'per hundred.' We use this symbol - % - for percents.

Let's take the word apart. It's per and cent. Where have you seen 'cent' before? Well, it's the word for a penny. It's also in the word century. What's a century? A hundred years. And then there's centennial; that's the 100-year anniversary. A centipede has 100 legs. Well, I think it does. I've never tried to count. And a woman who has centuplets is going to be crazy tired.

Let's talk about what percents mean. When you're hitting 99% of your shots, what did you do? If you took 100 shots, you made 99 of them. 99 per one hundred, per-cent. But what if you took 1,000 shots? Whoa. I bet your arms are tired. 99% means that you got 99 out of each hundred. So 99% of 1,000 is 990. Hitting 99% of your shots would also make you the best basketball player in the history of the world.

This is a stats-driven game, so let's talk about what we can do with percents. We can convert percents to fractions quite easily. For example, our team makes 43% of its free throws. Let's say we want to convert 43% to a fraction. That's 43 per one hundred. As a fraction, it's 43/100. That's it!

And then there's Fred the Flying Monkey, our team mascot. He jumps off a trampoline to make crazy dunks during halftime. He only makes 8% of his dunks. That sounds bad, but it's actually one of the best percentages among flying monkeys, with or without trampolines.

Anyway, if we had 8%, it'd be 8/100. No matter what your percent, just put it over 100, and you've made it into a fraction. With 8/100, we can simplify that to 2/25, which still doesn't sound great.

What about decimals? What is 43% as a decimal? Just drop the percent sign and move the decimal two places to the left. So 43% becomes .43. Why? Because .43 is 43 one-hundredths.

I said we make 43% of our free throws. What if we wanted to know what 43% of 17 is. We had 17 free throws in the last game. If we multiply 17 times .43, we get 7.31. The team made 8 of 17 free throws, so we were slightly above our average percentage.

What about 8%? I know, I know. Fred doesn't like to talk about it. But still, just drop the sign and move the decimal two places to the left. So 8% becomes .08. The math is the same. To figure out his success in 50 attempts, we'd multiply 50 times .08, which is 4. Hey, 4 is better than 0!

Let's try some practice problems involving percents. Just as there are different ways to win a basketball game, there are different ways to solve a percent problem. As we go through these, let's try a few different methods for solving them.

At a home game, 84% of the seats are filled. If there are 5,200 seats, how many seats are filled? To solve this, let's set up two fractions: 84/100 = *x*/5,200. Remember, 84% as a fraction is just 84/100. If we cross multiply, we get 100*x* = 436,800. Divide by 100, and we find out that 4,368 fans showed up.

We also could have converted 84% to a decimal. 84% would become .84. And then we just multiply .84 times 5,200, which is, again, 4,368.

Here's another one: If a team has 15 players and 9 travel for a road game, how many players stay home? This one has a little trick to it. Note that the question is asking how many players stay home. So instead of 9, we want 15 - 9, or 6. So what is 6 of 15?

If we set this up as a fraction, we have *x*/100 = 6/15. Cross multiply to get 15*x* = 600. 600 divided by 15 is 40. So 40/100 students stayed home. What is 40/100 as a percent? 40%. The bigger question is this: Where's the dedication on that team? 40% stayed home? Not cool.

Here's another one: In a game, a team makes 36 shots and misses 42. What percent of shots were made? The trick here is that we're not given the total. The fraction for the made shots isn't 36/42. It's 36/(36 + 42), so a total of 78 shots were attempted. To solve this one, let's try something different. Let's just divide 36 by 78. That gets us a decimal, .46. We can convert that to a percent by moving the decimal two places to the right. So .46 is 46%. The team made 46% of its shots.

To summarize, we learned about percents. 'Percent' means per hundred.

To convert a percent to a fraction, we just put the number over 100. 75% becomes 75/100. 2% becomes 2/100.

To convert a percent to a decimal, we drop the sign and move the decimal two places to the left. 15% becomes .15. 9% becomes .09.

Oh, and 110%? If 100% is the maximum you can give, how do you give 110%? Well, see, it's a metaphor. But that's a whole other topic...

After watching this lesson, you should be able to define percent and explain how to convert a percent to a fraction or decimal.

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
5 in chapter 3 of the course:

Back To Course

Algebra I: High School20 chapters | 168 lessons | 1 flashcard set

- Ratios & Rates: Definitions & Examples 6:37
- How to Solve Problems with Money 8:29
- Proportion: Definition, Application & Examples 6:05
- Calculations with Ratios and Proportions 5:35
- Percents: Definition, Application & Examples 6:20
- Math Combinations: Formula and Example Problems 7:14
- How to Calculate a Permutation 6:58
- How to Solve Problems with Time 6:18
- Distance Formulas: Calculations & Examples 6:31
- Go to High School Algebra: Calculations, Ratios, Percent & Proportions

- Computer Science 336: Network Forensics
- Computer Science 220: Fundamentals of Routing and Switching
- Global Competency Fundamentals & Applications
- Introduction to the Principles of Project Management
- Praxis Elementary Education: Reading & Language Arts - Applied CKT (7902): Study Guide & Practice
- Practical Applications for Business Ethics
- Practical Applications for Marketing
- Practical Applications for HR Management
- Practical Applications for Organizational Behavior
- Analyzing Texts Using Writing Structures
- MBLEx Prep Product Comparison
- AEPA Prep Product Comparison
- ASCP Prep Product Comparison
- NCE Prep Product Comparison
- TASC Test Score Information
- What is the TASC Test?
- Praxis Prep Product Comparison

- Diclofenac vs. Ibuprofen
- Developing & Managing a High-Quality Library Collection
- Library Space Planning
- Literacy Strategies for Teachers
- Arithmetic Operations in R Programming
- Practical Application: Understanding Employee Behavior
- Positive Global Outcomes of Global Competence
- Practical Application: Color Wheel Infographic
- Quiz & Worksheet - Developing a Learner-Centered Classroom
- Quiz & Worksheet - Technology for Teaching Reading
- Quiz & Worksheet - Pectoralis Major Anatomy
- Quiz & Worksheet - Oral & Written Communication Skills
- Quiz & Worksheet - How to Teach Reading to ELL Students
- Flashcards - Measurement & Experimental Design
- Flashcards - Stars & Celestial Bodies

- Math 105: Precalculus Algebra
- DSST Fundamentals of Counseling: Study Guide & Test Prep
- English Literature: Certificate Program
- SAT Subject Test Mathematics Level 2: Practice and Study Guide
- Middle School Life Science: Help and Review
- Writing Conventions - Usage: Help and Review
- Understanding Function Operations: Tutoring Solution
- Quiz & Worksheet - The Global Radiation Budget
- Quiz & Worksheet - Locke's Causal Theory of Perception
- Quiz & Worksheet - Politics and Economics in the People's Republic of China
- Quiz & Worksheet - What are the Stages of Perception?
- Quiz & Worksheet - DeVito's Six-Stage Model of Relationships

- Literary Genres: Definition, Types, Characteristics & Examples
- Types of Brain Scans
- Frindle Lesson Plan
- Red Scare Lesson Plan
- Arizona English Language Proficiency Standards & Levels
- NGSS Life Science for Middle School
- North Dakota State Standards for Math
- North Carolina Homeschool Laws
- Scholarships for Homeschoolers
- Texas Teacher Certification Renewal
- Texas Teacher Certification Renewal
- What are the NBPTS Standards?

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

Browse by subject