Percentages are a way of expressing a number as a fraction of 100. The word "percent" means "per hundred," so when we talk about percentages, we are talking about a number out of 100.

To convert a percentage to a decimal, divide the percentage by 100. For example, to convert 25% to a decimal, you would divide 25 by 100 to get 0.25.

To convert a decimal to a percentage, multiply the decimal by 100. For example, to convert 0.75 to a percentage, you would multiply 0.75 by 100 to get 75%.

To find a certain percentage of a number, you can multiply the number by the decimal equivalent of the percentage. For example, to find 20% of 150, you would multiply 150 by 0.20 to get 30.

To calculate the percentage increase or decrease between two numbers, you can use the following formula:

Percentage change = ((new number - original number) / original number) * 100

If the result is positive, it's a percentage increase. If it's negative, it's a percentage decrease.

- Understand the concept of percentages as fractions of 100.
- Practice converting between percentages and decimals.
- Learn how to find the percentage of a number.
- Practice calculating percentage increase or decrease using the formula.
- Work on real-world problems involving percentages, such as discounts, taxes, and tips.

Remember to use the conversion formulas, practice with sample problems, and apply the concepts to real-life situations to master the topic of percentages.

Study GuideIntroduction to Percent Worksheet/Answer key

Introduction to Percent Worksheet/Answer key

Introduction to Percent Worksheet/Answer key

Introduction to Percent Worksheet/Answer keyIntroduction to Percent

Number and Operations (NCTM)

Understand numbers, ways of representing numbers, relationships among numbers, and number systems.

Work flexibly with fractions, decimals, and percents to solve problems.

Develop meaning for percents greater than 100 and less than 1.

Grade 7 Curriculum Focal Points (NCTM)

Number and Operations and Algebra and Geometry: Developing an understanding of and applying proportionality, including similarity

Students extend their work with ratios to develop an understanding of proportionality that they apply to solve single and multi-step problems in numerous contexts. They use ratio and proportionality to solve a wide variety of percent problems, including problems involving discounts, interest, taxes, tips, and percent increase or decrease. They also solve problems about similar objects (including figures) by using scale factors that relate corresponding lengths of the objects or by using the fact that relationships of lengths within an object are preserved in similar objects. Students graph proportional relationships and identify the unit rate as the slope of the related line. They distinguish proportional relationships (y/x = k, or y = kx) from other relationships, including inverse proportionality (xy = k, or y = k/x).

Number and Operations and Algebra: Developing an understanding of operations on all rational numbers and solving linear equations

Students extend understandings of addition, subtraction, multiplication, and division, together with their properties, to all rational numbers, including negative integers. By applying properties of arithmetic and considering negative numbers in everyday contexts (e.g., situations of owing money or measuring elevations above and below sea level), students explain why the rules for adding, subtracting, multiplying, and dividing with negative numbers make sense. They use the arithmetic of rational numbers as they formulate and solve linear equations in one variable and use these equations to solve problems. Students make strategic choices of procedures to solve linear equations in one variable and implement them efficiently, understanding that when they use the properties of equality to express an equation in a new way, solutions that they obtain for the new equation also solve the original equation.

Connections to the Grade 7 Focal Points (NCTM)

Number and Operations: In grade 4, students used equivalent fractions to determine the decimal representations of fractions that they could represent with terminating decimals. Students now use division to express any fraction as a decimal, including fractions that they must represent with infinite decimals. They find this method useful when working with proportions, especially those involving percents. Students connect their work with dividing fractions to solving equations of the form ax = b, where a and b are fractions. Students continue to develop their understanding of multiplication and division and the structure of numbers by determining if a counting number greater than 1 is a prime, and if it is not, by factoring it into a product of primes.