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6º ano

No 6º ano, você começa a se tornar um matemágico sofisticado. Será capaz de somar, subtrair, multiplicar e dividir qualquer número que não seja negativo (inclusive decimais e frações), caso um ogro mal-humorado jogue algum deles em você. Ideias estonteantes, como expoentes (você os viu rapidamente no 5º ano), razões, porcentagens, números negativos e expressões variáveis, começarão a pertencer à sua zona de conforto. Mais importante, o lado algébrico da matemática é um novo tipo de diversão! E se isso não for suficiente, vamos continuar com nossa familiarização de conceitos, como o plano cartesiano (do 5º ano) e área, enquanto começamos a obter significado de dados! (O conteúdo dessa série foi selecionado com base em um currículo típico dos Estados Unidos.)
Perguntas da comunidade

Proporções, razões e porcentagens

A common application of numbers in real life (what is REAL life anyway, huh?) is through ratios, rates, and percentages. Whether following a recipe, changing the oil in a car, or determining the percentage earned a test...these are skills you will use over and over. Ratios are simply another way to express fractions. Rates combine units of measurements to help us understand their relationship better. Percentages, like ratios, give us another way to express fractions and decimals. We'll explain each to you and then practice until you've mastered each concept.

Operações aritméticas

The most fundamental branch of math is arithmetic operations. It consists of adding, subtracting, multiplying, and dividing numbers. We're willing to bet that doing these operations on whole numbers is a piece of cake, but now we'll mix those numbers up with decimals and fractions. We'll also introduce the idea exponents as they become much more important moving forward. So sharpen that pencil and relax in your chair, we're going for a ride!

Números negativos

Negative numbers are a necessary part of our understanding of mathematics and the world. The idea of anything "negative" is often seen as "bad." Negative numbers are not only good, but they're fun! Walk through this tutorial with us and we'll show you how they are defined, interpreted, and applied. Absolute value is a type of negative number that is expressed as a positive. Confused? Don't be. We got your back.

Propriedades dos números

This group of tutorials will introduce us to some of the common properties of numbers, including the least common multiple (LCM), greatest common factor (GCF), and the distributive property. All three of these will be extremely useful going forward. I know we ALWAYS say that...but really, it's true!

Variáveis e expressões

Learning algebra is a little like learning another language. In place of words, algebra often uses symbols in the forms of variables (letters) which are sometimes combined with numbers to form expressions (words/phrases) and combined further to create equations or inequalities (sentences). Ok, that comparison may have a few flaws, but you get the idea. In this group of tutorials, we'll learn about and practice writing, evaluating, and adding expressions; order of operations; substitution; combining like terms; and solving equations and understanding inequalities.

Geometria

Here in 6th grade, we start to really understand the fundamentals of Euclidian Geometry. As we've said before, the world around you is built with geometric shapes. Heck, even YOU are built with geometric shapes! Having an appreciation and understanding of how we study, measure, and create these shapes helps us to improve our lives. In this group of tutorials we'll explore plotting points and interpreting the coordinate plane; and measuring area, volume, and surface area of geometric shapes--including different types of polygons.

Dados e estatísticas

In statistics, we try to make sense of the world by collecting, organizing, analyzing, and presenting large amounts of data. For example, you may survey your friends about what tv show is most popular, but the small sample size will not give you an accurate idea of what ALL 6th graders like to watch. To do this you must survey a cross section of students from all around the country and all backgrounds. The data can then be statistically analyzed to give a more accurate picture of what tv show is most popular. So let's dive into a discussion of statistics, including box and whisker plots, bar charts, pictographs, line graphs, and dot plots.
Variáveis e expressões
Learning algebra is a little like learning another language. In place of words, algebra often uses symbols in the forms of variables (letters) which are sometimes combined with numbers to form expressions (words/phrases) and combined further to create equations or inequalities (sentences). Ok, that comparison may have a few flaws, but you get the idea. In this group of tutorials, we'll learn about and practice writing, evaluating, and adding expressions; order of operations; substitution; combining like terms; and solving equations and understanding inequalities.
Conteúdo completo em “Variáveis e expressões”

Cálculo de expressões numéricas

Mathematics wouldn't be so useful if, interpreted in different ways, the same expression could be viewed to represent different values. To combat this issue, the mathematical community defined "orders of operations" to remove ambiguity when evaluating an expression. Our acronym is PEMDAS: parentheses, exponents, multiplication, division, addition, and subtraction. Get it? Of course you. Let's talk more about order of operation and how will apply it.

Cálculo de expressões com variáveis

Wait, why are we using letters in math? How can an 'x' represent a number? What number is it? I must figure this out!!! Yes, you must. This tutorial is great if you're just beginning to delve into the world of algebraic variables and expressions. It will help guide your understanding of how variables can be substituted with different values and therefore giving us different outcomes. Common Core Standards: 6.EE.A.1, 6.EE.A.2b, 6.EE.A.2c

Expressões equivalentes

Using the combined powers of Chuck Norris and polar bears (which are much less powerful than Mr. Norris) to better understand what expressions represent and how we can manipulate them. We'll achieve a good understanding of the concept of "like terms" and combining expressions. Great tutorial if you want to understand that expressions are just a way to express things! Common Core Standards: 6.EE.A.3, 6.EE.A.4

Resolução de equações e inequações com substituição

The core underlying concepts in algebra are variables, expressions, equations and inequalities. You will see them throughout your math life (and even life after school). This tutorial won't give you all the tools that you'll later learn to analyze and interpret these ideas, but it'll get you started thinking about them. Common Core Standards: 6.EE.B.5, 6.EE.B.6, 6.EE.B.7

Solving basic equations

Much of algebra seems obsessed with "doing the same thing to both sides". Why is this? How can we develop an intuition for which algebraic operations are valid and which ones aren't? This tutorial takes a high-level, conceptual walk-through of what an equation represents and why we do the same thing to both sides of it. Common Core Standard: 6.EE.B.7

Variables and equations word problem: Super Yoga

Let's use our algebra tools to solve a problem of earth-shattering importance: which Super Yoga plan is the best value! In this word problem, you'll put to practice your knowledge of variables, substitution, and one-step equations. Common Core Standard: 6.EE.B.6

Solving equations for beginners

Like previous tutorials in this topic, we'll introduce you to the most fundamental ideas of what equations mean and how to solve them. We'll then do a bunch of examples to make sure you're comfortable with things like 3x – 7 = 8. So relax, grab a cup of hot chocolate, and be on your way to becoming an algebra rockstar. And, by the way, in any of the "example" videos, try to solve the problem on your own before seeing how Sal does it. It makes the learning better! Common Core Standard: 6.EE.B.7

Variáveis dependentes e independentes

We know that anything that is "independent" is not affected by other "dependent" forces. In math relationships (and algebra, in particular), one variable (the independent one) is thought to drive the behavior of the other one (the dependent one). This tutorial explores that relationship and how it can be expressed and interpreted. Common Core Standards: 6.EE.C.9

Inequações

Not all expressions are created equal, but we can still use some algebra to compare unequal numbers, variables, and/or expressions in interesting ways, like inequalities. You've heard of "greater than" and "less than," right? Terrific! First we'll express inequalities on a number line and then write them using information in word problems. Common Core Standard: 6.EE.B.8