Solving A Proportion With An Unknown Variable (example) | 7th Grade | Khan Academy

Here’s a great video where we explain the reasoning behind solving proportions. We’ll put some algebra to work to get our answers, too. Practice this lesson yourself on KhanAcademy.org right now: Watch the next lesson: Missed the previous lesson? Grade 7th on Khan Academy: 7th grade takes much of what you learned in 6th grade to an entirely new level. In particular, you’ll now learn to do everything with negative numbers (we’re talking everything–adding, subtracting, multiplying, dividing, fractions, decimals… everything!). You’ll also take your algebraic skills to new heights by tackling two-step equations. 7th grade is also when you start thinking about probability (which is super important for realizing that casinos and lotteries are really just ways of taking money away from people who don’t know probability) and dig deeper into the world of data and statistics. Onward! (Content was selected for this grade level based on a typical curriculum in the United States.) About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We’ve also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to Khan Academy‰Ûªs 7th grade channel: Subscribe to Khan Academy:

Graphs Of Linear Equations | Linear Equations And Functions | 8th Grade | Khan Academy

Practice this lesson yourself on KhanAcademy.org right now: Watch the next lesson: Missed the previous lesson? 8th grade on Khan Academy: 8th grade is all about tackling the meat of algebra and getting exposure to some of the foundational concepts in geometry. If you get this stuff (and you should because you’re incredibly persistent), the rest of your life will be easy. Okay, maybe not your whole life, but at least your mathematical life. Seriously, if you really get the equations and functions stuff we cover here, most of high school will feel intuitive, even relaxing. (Content was selected for this grade level based on a typical curriculum in the United States.) About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We’ve also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to Khan Academy’s 8th grade channel: Subscribe to Khan Academy:

Solving Linear Systems By Graphing | Systems Of Equations | 8th Grade | Khan Academy

Solving Linear Systems by Graphing Practice this lesson yourself on KhanAcademy.org right now: Watch the next lesson: Missed the previous lesson? 8th grade on Khan Academy: 8th grade is all about tackling the meat of algebra and getting exposure to some of the foundational concepts in geometry. If you get this stuff (and you should because you’re incredibly persistent), the rest of your life will be easy. Okay, maybe not your whole life, but at least your mathematical life. Seriously, if you really get the equations and functions stuff we cover here, most of high school will feel intuitive, even relaxing. (Content was selected for this grade level based on a typical curriculum in the United States.) About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We’ve also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to Khan Academy’s 8th grade channel: Subscribe to Khan Academy:

The Substitution Method | Systems Of Equations | 8th Grade | Khan Academy

The Substitution Method Practice this lesson yourself on KhanAcademy.org right now: Watch the next lesson: Missed the previous lesson? 8th grade on Khan Academy: 8th grade is all about tackling the meat of algebra and getting exposure to some of the foundational concepts in geometry. If you get this stuff (and you should because you’re incredibly persistent), the rest of your life will be easy. Okay, maybe not your whole life, but at least your mathematical life. Seriously, if you really get the equations and functions stuff we cover here, most of high school will feel intuitive, even relaxing. (Content was selected for this grade level based on a typical curriculum in the United States.) About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We’ve also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to Khan Academy’s 8th grade channel: Subscribe to Khan Academy:

Probability Explained | Independent And Dependent Events | Probability And Statistics | Khan Academy

We give you an introduction to probability through the example of flipping a quarter and rolling a die. Practice this lesson yourself on KhanAcademy.org right now: Watch the next lesson: Probability and statistics on Khan Academy: We dare you to go through a day in which you never consider or use probability. Did you check the weather forecast? Busted! Did you decide to go through the drive through lane vs walk in? Busted again! We are constantly creating hypotheses, making predictions, testing, and analyzing. Our lives are full of probabilities! Statistics is related to probability because much of the data we use when determining probable outcomes comes from our understanding of statistics. In these tutorials, we will cover a range of topics, some which include: independent events, dependent probability, combinatorics, hypothesis testing, descriptive statistics, random variables, probability distributions, regression, and inferential statistics. So buckle up and hop on for a wild ride. We bet you’re going to be challenged AND love it! About Khan Academy: Khan Academy is a nonprofit with a mission to provide a free, world-class education for anyone, anywhere. We believe learners of all ages should have unlimited access to free educational content they can master at their own pace. We use intelligent software, deep data analytics and intuitive user interfaces to help students and teachers around the world. Our resources cover preschool through early college education, including math, biology, chemistry, physics, economics, finance, history, grammar and more. We offer free personalized SAT test prep in partnership with the test developer, the College Board. Khan Academy has been translated into dozens of languages, and 100 million people use our platform worldwide every year. For more information, visit join us on Facebook or follow us on Twitter at @khanacademy. And remember, you can learn anything. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to KhanAcademy’s Probability and Statistics channel: Subscribe to KhanAcademy:

Rounding Decimals: To The Nearest Tenth | Decimals | Pre-Algebra | Khan Academy

Rounding. Oh my….there will be so many times when rounding numbers (including decimals) will be a required skill. Let’s get this down, shall we? Practice this lesson yourself on KhanAcademy.org right now: Watch the next lesson: Missed the previous lesson? Pre-Algebra on Khan Academy: No way, this isn’t your run of the mill arithmetic. This is Pre-algebra. You’re about to play with the professionals. Think of pre-algebra as a runway. You’re the airplane and algebra is your sunny vacation destination. Without the runway you’re not going anywhere. Seriously, the foundation for all higher mathematics is laid with many of the concepts that we will introduce to you here: negative numbers, absolute value, factors, multiples, decimals, and fractions to name a few. So buckle up and move your seat into the upright position. We’re about to take off! About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We’ve also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to KhanAcademy’s Pre-Algebra channel:: Subscribe to KhanAcademy:

Basic Trigonometry | Basic Trigonometry | Trigonometry | Khan Academy

Introduction to trigonometry Practice this lesson yourself on KhanAcademy.org right now: Watch the next lesson: Trigonometry on Khan Academy: Big, fancy word, right? Don’t be fooled. Looking at the prefix, tri-, you could probably assume that trigonometry (“trig” as it’s sometimes called) has something to do with triangles. You would be right! Trig is the study of the properties of triangles. Why is it important? It’s used in measuring precise distances, particularly in industries like satellite systems and sciences like astronomy. It’s not only space, however. Trig is present in architecture and music, too. Now you may wonder…how is knowing the measurement and properties of triangles relevant to music?? THAT is a great question. Maybe you’ll learn the answer from us in these tutorials! About Khan Academy: Khan Academy is a nonprofit with a mission to provide a free, world-class education for anyone, anywhere. We believe learners of all ages should have unlimited access to free educational content they can master at their own pace. We use intelligent software, deep data analytics and intuitive user interfaces to help students and teachers around the world. Our resources cover preschool through early college education, including math, biology, chemistry, physics, economics, finance, history, grammar and more. We offer free personalized SAT test prep in partnership with the test developer, the College Board. Khan Academy has been translated into dozens of languages, and 100 million people use our platform worldwide every year. For more information, visit join us on Facebook or follow us on Twitter at @khanacademy. And remember, you can learn anything. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to Khan Academy’s Trigonometry channel: Subscribe to Khan Academy:

Lattice Multiplication | Multiplication And Division | Arithmetic | Khan Academy

Introduction to lattice multiplication Watch the next lesson: Missed the previous lesson? Arithmetic on Khan Academy: So you’re ready to have some arithmetic fun? You’ve come to the right spot! It’s the first “official” math topic and chalked full of fun exercises and great videos which help you start your journey towards math mastery. We’ll cover the big ones: addition, subtraction, multiplication, and division, of course. But we don’t stop there. We’ll get into negative numbers, absolute value, decimals, and fractions, too. Learning math should be fun, and we plan on having some with you. Ready to get started? About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We’ve also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to KhanAcademy’s Arithmetic channel: Subscribe to KhanAcademy:

Cutting Shapes Into Equal Parts | Math | 3rd Grade | Khan Academy

Lindsay figures out if 4 pieces of pie are each equal to 1/4 of the pie. Practice this yourself on Khan Academy right now: Watch the next lesson: Missed the previous lesson? Watch here: 3rd grade math on Khan Academy: We know you’ve been rocking through 2nd grade adding and subtracting all kinds of whole numbers (up to 2 digits, right?). That’s awesome! In 3rd grade math we want you to start using bigger numbers and start multiplying and dividing, too. By the way, did you know that some numbers aren’t actually “whole?” They’re “partially whole.” We call them fractions! We want you to start playing around and having fun with those, too. There’s also area, perimeter, and place value to be discovered. Whew. We have so much to do and can’t wait to do it with you. Let’s go! Want a virtual coach for 3rd grade? Unlock the 3rd grade mission on Khan Academy here: About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We’ve also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to KhanAcademy:

Counting American Coins | Measurement And Data | Early Math | Khan Academy

Practice this lesson yourself on KhanAcademy.org right now: Watch the next lesson: Missed the previous lesson? Early Math on Khan Academy: Math begins with counting. It’s the most important skill we learn in our early years and becomes the foundation for all other math concepts. Once we can count, we can add, subtract, and measure the world around us. Shortly thereafter, we can learn about place values, plots, graphs, time, money, and shapes. These early math skills are presented in this subject’s tutorials in a straightforward, understandable, and (dare we say it) fun way! Want a virtual coach for Early Math? Unlock the Early Math mission on Khan Academy here: About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We’ve also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to KhanAcademy’s Early Math channel: Subscribe to KhanAcademy: