Cosmology & Astronomy on Khan Academy: The Earth is huge, but it is tiny compared to the Sun (which is super huge). But the Sun is tiny compared to the solar system which is tiny compared to the distance to the next star. Oh, did we mention that there are over 100 billion stars in our galaxy (which is about 100,000 light years in diameter) which is one of hundreds of billions of galaxies in just the observable universe (which might be infinite for all we know). Don't feel small. We find it liberating. Your everyday human stresses are nothing compared to this enormity that we are a part of. Enjoy the fact that we get to be part of this vastness!
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.
When we compare numbers we use the concepts of greater than, less than, and equal to (=). The same is true of absolute values.
Practice this lesson yourself on KhanAcademy.org right now: https://www.khanacademy.org/math/arithmetic/absolute-value/abs_value_tutorial/e/comparing_absolute_values?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra
Watch the next lesson: https://www.khanacademy.org/math/arithmetic/absolute-value/abs_value_tutorial/v/absolute-value-word-problems-exercise?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra
Missed the previous lesson?
https://www.khanacademy.org/math/arithmetic/absolute-value/abs_value_tutorial/v/absolute-value-of-integers?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra
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!
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https://www.youtube.com/watch?v=hKkBlcnU9pw
Note: All Khan Academy content is available for free at (www.khanacademy.org)
How many times have you been told, "Save your money!" We thought so. What if you wanted to save a fractional amount of your allowance? How would you go about figuring out how much to save?
Practice this lesson yourself on KhanAcademy.org right now: https://www.khanacademy.org/math/pre-algebra/fractions-pre-alg/equivalent-fractions-pre-alg/e/equivalent_fractions?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra
Watch the next lesson: https://www.khanacademy.org/math/pre-algebra/fractions-pre-alg/equivalent-fractions-pre-alg/v/finding-common-denominators?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra
Missed the previous lesson?
https://www.khanacademy.org/math/pre-algebra/fractions-pre-alg/equivalent-fractions-pre-alg/v/equivalent-fractions?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra
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!
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https://www.youtube.com/watch?v=0JW9P_T4P_Y
Note: All Khan Academy content is available for free at (www.khanacademy.org)
Showing that a triangle with the same point as the orthocenter and centroid is equilateral
Watch the next lesson: https://www.khanacademy.org/math/geometry/triangle-properties/triangle_property_review/v/review-of-triangle-properties?utm_source=YT&utm_medium=Desc&utm_campaign=Geometry
Missed the previous lesson?
https://www.khanacademy.org/math/geometry/triangle-properties/altitudes/v/proof-triangle-altitudes-are-concurrent-orthocenter?utm_source=YT&utm_medium=Desc&utm_campaign=Geometry
Geometry on Khan Academy: We are surrounded by space. And that space contains lots of things. And these things have shapes. In geometry we are concerned with the nature of these shapes, how we define them, and what they teach us about the world at large--from math to architecture to biology to astronomy (and everything in between). Learning geometry is about more than just taking your medicine ("It's good for you!"), it's at the core of everything that exists--including you. Having said all that, some of the specific topics we'll cover include angles, intersecting lines, right triangles, perimeter, area, volume, circles, triangles, quadrilaterals, analytic geometry, and geometric constructions. Wow. That's a lot. To summarize: it's difficult to imagine any area of math that is more widely used than geometry.
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.
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https://www.youtube.com/watch?v=pDZIvyeqX1o
Note: All Khan Academy content is available for free at (www.khanacademy.org)
How banks can actually create checking accounts under a fractional reserve system
Watch the next lesson: https://www.khanacademy.org/economics-finance-domain/macroeconomics/monetary-system-topic/factional-reserve-accounting/v/simple-fractional-reserve-accounting-part-1?utm_source=YT&utm_medium=Desc&utm_campaign=macroeconomics
Missed the previous lesson? https://www.khanacademy.org/economics-finance-domain/macroeconomics/monetary-system-topic/factional-reserve-accounting/v/simple-fractional-reserve-accounting-part-1?utm_source=YT&utm_medium=Desc&utm_campaign=macroeconomics
Macroeconomics on Khan Academy: Topics covered in a traditional college level introductory macroeconomics course
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.
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https://www.youtube.com/watch?v=PASajlCGBTw
Note: All Khan Academy content is available for free at (www.khanacademy.org)
Seeing what happens to quantity demanded when price changes
Watch the next lesson: https://www.khanacademy.org/economics-finance-domain/microeconomics/choices-opp-cost-tutorial/marginal-utility-tutorial/v/budget-line?utm_source=YT&utm_medium=Desc&utm_campaign=microeconomics
Missed the previous lesson? https://www.khanacademy.org/economics-finance-domain/microeconomics/choices-opp-cost-tutorial/marginal-utility-tutorial/v/equalizing-marginal-utility-per-dollar-spent?utm_source=YT&utm_medium=Desc&utm_campaign=microeconomics
Microeconomics on Khan Academy: Topics covered in a traditional college level introductory microeconomics course
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.
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https://www.youtube.com/watch?v=4-_-wQc3EGE
Note: All Khan Academy content is available for free at (www.khanacademy.org)
Example of constructing hypotheses for a test about a mean.
View more lessons or practice this subject at http://www.khanacademy.org/math/ap-statistics/tests-significance-ap/one-sample-t-test-mean/v/writing-hypotheses-for-significance-test-about-means?utm_source=youtube&utm_medium=desc&utm_campaign=apstatistics
AP Statistics on Khan Academy: Meet one of our writers for AP¨_ Statistics, Jeff. A former high school teacher for 10 years in Kalamazoo, Michigan, Jeff taught Algebra 1, Geometry, Algebra 2, Introductory Statistics, and AP¨_ Statistics. Today he's hard at work creating new exercises and articles for AP¨_ Statistics.
Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help! Donate or volunteer today!
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https://www.youtube.com/watch?v=89Dp9Xq4eaA
Note: All Khan Academy content is available for free at (www.khanacademy.org)
Part 3 of the presentation on age word problems
Watch the next lesson: https://www.khanacademy.org/math/algebra/linear_inequalities/inequalities/v/inequalities-using-multiplication-and-division?utm_source=YT&utm_medium=Desc&utm_campaign=AlgebraI
Missed the previous lesson?
https://www.khanacademy.org/math/algebra/solving-linear-equations-and-inequalities/old-school-equations/v/age-word-problems-2?utm_source=YT&utm_medium=Desc&utm_campaign=AlgebraI
Algebra I on Khan Academy: Algebra is the language through which we describe patterns. Think of it as a shorthand, of sorts. As opposed to having to do something over and over again, algebra gives you a simple way to express that repetitive process. It's also seen as a "gatekeeper" subject. Once you achieve an understanding of algebra, the higher-level math subjects become accessible to you. Without it, it's impossible to move forward. It's used by people with lots of different jobs, like carpentry, engineering, and fashion design. In these tutorials, we'll cover a lot of ground. Some of the topics include linear equations, linear inequalities, linear functions, systems of equations, factoring expressions, quadratic expressions, exponents, functions, and ratios.
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.
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https://www.youtube.com/watch?v=DplUpe3oyWo
Starting with the reign of Augustus and ending with the reign of Marcus Aurelius, the Pax Romana is a relatively stable 200 year period. The first five emperors are of the Julio-Claudia Dynasty. The last five of the Pax Romana are considered the "good" emperors by Machiavelli.
Watch the next lesson: https://www.khanacademy.org/humanities/world-history/ancient-medieval/roman-empire-survey/v/fall-of-the-roman-empire
World History on Khan Academy: From the earliest civilizations to the modern world, geography, religion, trade, and politics have bound peoples and nations together — and torn them apart. Take a journey through time and space and discover the fascinating history behind the complex world we inhabit today.
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
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https://www.youtube.com/watch?v=sF3Lh4XT4hg
Note: All Khan Academy content is available for free at (www.khanacademy.org)
Learn how to convert fractions from tenths to hundredths using grid diagrams.
Practice this lesson yourself on KhanAcademy.org right now:
https://www.khanacademy.org/math/cc-fourth-grade-math/cc-4th-fractions-topic/cc-4th-fractions-unlike-denom/e/equivalent-fractions-with-denominators-of-10-and-100-intuition?utm_source=YT&utm_medium=Desc&utm_campaign=4thgrade
Watch the next lesson: https://www.khanacademy.org/math/cc-fourth-grade-math/cc-4th-fractions-topic/cc-4th-fractions-unlike-denom/v/decomposing-hudredths-into-tenths-and-hundredths?utm_source=YT&utm_medium=Desc&utm_campaign=4thgrade
Missed the previous lesson? https://www.khanacademy.org/math/cc-fourth-grade-math/cc-4th-fractions-topic/cc-4th-mult-whole-frac-word-problems/v/multiplying-fractions-word-problem-2?utm_source=YT&utm_medium=Desc&utm_campaign=4thgrade
Grade 4th on Khan Academy: 4th grade is the time to start really fine-tuning your arithmetic skills. Not only will you be a multi-digit addition and subtraction rockstar, but you'll extend the multiplication and division that you started in 3rd grade to several digits. You'll also discover that you sometimes have something left over (called a "remainder") when you divide. In 3rd grade you learned what a fraction is. Now you'll start adding, subtracting, multiplying, and comparing them. You'll also see how they relate to decimals. On other fronts, you'll learn how to convert between different units (which is super important when comparing the size and speed of robot unicorns in different countries) and continue your journey thinking about various shapes in two dimensions. Some of the foundational concepts of geometry (like lines, rays and angles) also get introduced. As always, we'll round this out with a healthy dose of applied word problems and explorations of number patterns and properties (including the ideas of factors, multiples and prime numbers). The fun must not stop! (Content was selected for this grade level based on a typical curriculum in the United States.)
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https://www.youtube.com/watch?v=zEd67cLFnuQ
Note: All Khan Academy content is available for free at (www.khanacademy.org)