Ch 12: Decimals, Percents & Ratios

About This Chapter

Brush up on your understanding of operations with decimals, percents and ratios. Look at how to convert between decimals and percents, and review methods of calculating with proportions.

Decimals, Percents & Ratios - Chapter Summary

In this chapter's lessons, our instructors explain how to solve problems with decimal numbers and percents, and refresh your knowledge of how to change between percents, decimals and fractions. You'll review how to solve interest problems and word problems with percents. Other lessons look at ratios and proportions, including how to perform calculations with them. After you've watched these videos, you should be ready to:

  • Solve problems with decimal numbers
  • Perform conversions involving percents, fractions and decimals
  • Understand word problems with percents
  • Explain the steps in solving interest problems
  • Define proportion and how it is used
  • Execute calculations with proportions and ratios

These lessons are brief and contain plenty of examples to explain their points. You can study on a computer or mobile device as your schedule permits. The quizzes at the end of each lesson allow you to gauge your knowledge and determine what calls for extra study.

10 Lessons in Chapter 12: Decimals, Percents & Ratios
Test your knowledge with a 30-question chapter practice test
What is a Percent? - Definition & Examples

1. What is a Percent? - Definition & Examples

Thinking in terms of pizza is an excellent way to think about percentages. Learn how it can help you understand percentages in this video lesson. You will also learn about the uses of percentages in the real world.

Changing Between Decimals and Percents

2. Changing Between Decimals and Percents

Watch as we go on a rollercoaster ride in changing from a decimal to percent and then back again. Learn to master this technique so you can get as fast as a rollercoaster going downhill on tests and quizzes when you have to convert between the two.

Converting Percent Notation to Fraction Notation

3. Converting Percent Notation to Fraction Notation

The process of converting percents to fractions is quite easy if you know where to start. This lesson will show you how to perform the conversion and give some real-world examples.

Converting Fractions to Percents

4. Converting Fractions to Percents

There are times when it is important to know how to convert a fraction to a percent. Fortunately, the steps to perform this conversion are not difficult. This lesson will show you those steps and give some examples.

Solve Problems Using Percents

5. Solve Problems Using Percents

Percents are your friend. Think of all the cool things percents do for you. They save you money, and they tell you how well you are doing in school. Learn how you can solve problems with percents in this video lesson.

How to Solve Word Problems That Use Percents

6. How to Solve Word Problems That Use Percents

100 percent of percent problems can be solved if we follow the correct steps. In this lesson, we'll practice solving a variety of different percent problems.

How to Solve Interest Problems: Steps & Examples

7. How to Solve Interest Problems: Steps & Examples

If you want to know how your money can earn money, then it's essential to learn about solving interest problems. In this lesson, we'll practice calculating interest amounts and interest rates.

Proportion: Definition, Application & Examples

8. Proportion: Definition, Application & Examples

When we want to compare one ratio, or fraction, to another equivalent ratio, it's a proportion. Learn all about proportions and practice solving proportion problems in this lesson.

Ratios & Rates: Definitions & Examples

9. Ratios & Rates: Definitions & Examples

If we have two items, or two numbers, and we want to compare them, what language can we use? How do we write the comparison? Find out as we learn about ratios and rates in this lesson.

Calculations with Ratios and Proportions

10. Calculations with Ratios and Proportions

Even if only 99 out of 100 people need to know how to work with ratios, the odds that they'll be useful to you are very high. In this lesson, we'll practice performing calculations with ratios and proportions.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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