# Ch 21: GRE - Probability & Statistics: Help & Review

### About This Chapter

## Who's it for?

Anyone who needs help learning or mastering GRE material will benefit from taking this course. There is no faster or easier way to acquire the skills needed to take the GRE. Among those who would benefit are:

- Students who have fallen behind in understanding operations involving probability and statistics
- Students who struggle with learning disabilities or learning differences, including autism and ADHD
- Students who prefer multiple ways of learning math (visual or auditory)
- Students who have missed class time and need to catch up
- Students who need an efficient way to learn about probability and statistics
- Students who struggle to understand their teachers
- Students who attend schools without extra math learning resources

## How it works:

- Find videos in our course that cover what you need to learn or review.
- Press play and watch the video lesson.
- Refer to the video transcripts to reinforce your learning.
- Test your understanding of each lesson with short quizzes.
- Verify you're ready by completing the Probability and Statistics chapter exam.

## Why it works:

**Study Efficiently:**Skip what you know, review what you don't.**Retain What You Learn:**Engaging animations and real-life examples make topics easy to grasp.**Be Ready on Test Day:**Use the Probability and Statistics chapter exam to be prepared.**Get Extra Support:**Ask our subject-matter experts any question about probability and statistics. They're here to help!**Study With Flexibility:**Watch videos on any web-ready device.

## Students will review:

This chapter helps students review the concepts in a probability and statistics unit of a standard GRE prep course. Topics covered include:

- Calculating mean, median and range
- Determining probability of simple, compound and complementary events
- Calculating probability of combinations and permutations
- Calculating probability of independent and dependent events
- Calculating permutations
- Understanding standard deviation and shifts in the mean
- Using relative and cumulative frequency tables
- Calculating simple conditional probabilities

### 1. Understanding Bar Graphs and Pie Charts

In this lesson, we will examine two of the most widely used types of graphs: bar graphs and pie charts. These two graphs can provide the reader with a comparison of the different data that is displayed.

### 2. How to Calculate Mean, Median, Mode & Range

Measures of central tendency can provide valuable information about a set of data. In this lesson, explore how to calculate the mean, median, mode and range of any given data set.

### 3. Probability of Simple, Compound and Complementary Events

Simple, compound, and complementary events are different types of probabilities. Each of these probabilities are calculated in a slightly different fashion. In this lesson, we will look at some real world examples of these different forms of probability.

### 4. How to Calculate the Probability of Combinations

To calculate the probability of a combination, you will need to consider the number of favorable outcomes over the number of total outcomes. Combinations are used to calculate events where order does not matter. In this lesson, we will explore the connection between these two essential topics.

### 5. How to Calculate the Probability of Permutations

In this lesson, you will learn how to calculate the probability of a permutation by analyzing a real-world example in which the order of the events does matter. We'll also review what a factorial is. We will then go over some examples for practice.

### 6. Probability of Independent and Dependent Events

Sometimes probabilities need to be calculated when more than one event occurs. These types of compound events are called independent and dependent events. Through this lesson, we will look at some real-world examples of how to calculate these probabilities.

### 7. Factorial Practice Problems

While the definition of factorial isn't complicated, it's easy to make them trickier by throwing a lot of them together and adding in some fractions. Test your skills here with some algebraic examples that make you use factorials without many numbers.

### 8. What Is a Factorial?

Maybe it's because I'm a math teacher, but when I watched the Olympics I found myself thinking about how many different ways the swimmers could have finished the race. In this video, you'll learn the answer to this question, why it's important and how it lead to the invention of the mathematical operation called the factorial.

### 9. Math Combinations: Formula and Example Problems

Combinations are an arrangement of objects where order does not matter. In this lesson, the coach of the Wildcats basketball team uses combinations to help his team prepare for the upcoming season.

### 10. How to Calculate a Permutation

A permutation is a method used to calculate the total outcomes of a situation where order is important. In this lesson, John will use permutations to help him organize the cards in his poker hand and order a pizza.

### 11. Probability of Independent Events: The 'At Least One' Rule

Occasionally when calculating independent events, it is only important that the event happens once. This is referred to as the 'At Least One' Rule. To calculate this type of problem, we will use the process of complementary events to find the probability of our event occurring at least once.

### 12. Either/Or Probability: Overlapping and Non-Overlapping Events

Statistics is the study and interpretation of a set of data. One area of statistics is the study of probability. This lesson will describe how to determine the either/or probability of overlapping and non-overlapping events.

### 13. Calculating the Standard Deviation

In this lesson, we will examine the meaning and process of calculating the standard deviation of a data set. Standard deviation can help to determine if the data set is a normal distribution.

### 14. How to Calculate Percent Increase with Relative & Cumulative Frequency Tables

In statistics, one way to describe and analyze data is by using frequency tables. This lesson will discuss relative and cumulative frequencies and how to calculate percent increase using these two methods.

### 15. How to Calculate Simple Conditional Probabilities

Conditional probability, just like it sounds, is a probability that happens on the condition of a previous event occurring. To calculate conditional probabilities, we must first consider the effects of the previous event on the current event.

### 16. Analysis Of Variance (ANOVA): Examples, Definition & Application

In this lesson, we will explain the most common statistical procedure in the field of psychology, the analysis of variance (ANOVA), in a way that's easy to understand. Then test your knowledge with a quiz.

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### Other Chapters

Other chapters within the GRE Prep: Help and Review course

- GRE Verbal Reasoning - Reading Skills: Help and Review
- GRE Verbal Reasoning - Vocabulary Skills: Help and Review
- GRE Analytical Writing - Crafting Your Argument: Help and Review
- GRE Analytical Writing - Planning Your Essay: Help and Review
- GRE Analytical Writing - Starting Your Essay: Help and Review
- GRE Analytical Writing - Writing the Essay Body: Help and Review
- GRE Analytical Writing - Editing Your Essay: Help and Review
- GRE Analytical Writing - Writing Technique: Help and Review
- GRE Analytical Writing - Writing Stronger Sentences: Help and Review
- GRE Analytical Writing - Grammar and Usage: Help and Review
- GRE Quantitative Reasoning - Numbers and Operations: Help and Review
- GRE Quantitative Reasoning - Sequences and Series: Help and Review
- GRE - Equations and Expressions: Help and Review
- GRE - FOIL, Parabolas & Quadratics: Help & Review
- GRE Quantitative Reasoning - Exponents: Help and Review
- GRE Quantitative Reasoning - Functions: Help and Review
- GRE - Rational Equations & Expressions: Help & Review
- GRE Quantitative Reasoning - Inequalities: Help and Review
- GRE Quantitative Reasoning - Plane Geometry: Help and Review
- GRE Quantitative Reasoning - Coordinate Geometry: Help and Review
- GRE Quantitative Reasoning - Sets: Help and Review