# Ch 27: GRE Quantitative Reasoning: Probability and Statistics

### About This Chapter

## GRE Quantitative Reasoning: Probability and Statistics - Chapter Summary

Develop proficiency in determining probability and statistics with these GRE review tutorials. Video lectures address various statistical methods and concepts you'll need to know when answering questions on the quantitative part of the GRE. Topics covered in the probability and statistics materials include:

- Bar graphs
- Pie charts
- Central tendency measures
- Factorials
- Combination probability
- Permutation probability
- Frequency tables
- Conditional probability

The videos in this chapter comprise instruction in a variety of methods for discerning statistics and probabilities. In addition, complementary quizzes and practice problems can help you gauge your assimilation of the lessons. Chapter information is allocated into short, on-point videos covering individual topics to support your GRE success.

### GRE Quantitative Reasoning Objectives

The GRE is intended to determine how academically prepared you are to pursue a business or graduate school program. A little over one-third of the test contains questions related to quantitative reasoning, which may address areas of data analysis, geometry, arithmetic, or algebra. Our instructional probability and statistics videos help you understand quantitative concepts you'll find on the actual GRE. Following are some of the particular objectives addressed in these lessons:

- Interpreting pie charts and bar graphs
- Determining mean, mode, range, and median
- Understanding factorials
- Establishing the probability of different kinds of events
- Deducing the probability of a given permutation
- Ascertaining standard deviation
- Determining conditional probability

Questions on the quantitative reasoning segment of the GRE occur in a few different formats. There are multiple-choice questions with a single correct answer, multiple-choice questions with more than one right response, and multiple-choice questions that offer a pair of quantities and ask you to choose the answer that best describes the relationship between them. Lastly, there are numeric-entry questions that require the calculation and provision of an original numeric response.

### 1. Understanding Bar Graphs and Pie Charts

Bar graphs and pie charts are some of the most used graphical ways to present data. Learn how to read bar graphs and pie charts, and explore some examples to understand how they are interpreted.

### 2. Mean, Median, Mode & Range

The four most common measures of central tendency are the mean, median, mode, and range. Understand and calculate the mean, median, mode, and range through the given sample problems.

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

Probability can be calculated for simple, compound, and complementary events. Explore each type of event, understand how each event differs from the other types, and learn how to calculate each type of event's probability by reviewing examples.

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

The probability of combinations may be calculated when the order of the outcomes does not matter, using the number of favorable outcomes divided by total outcomes. Learn how to calculate the probability of combinations by working through helpful example problems.

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

A permutation calculates the number of outcomes where order of events matters, but not all outcomes are equally probable or favorable. Learn how to calculate the probability of permutations using functions and factorials.

### 6. Probability of Independent and Dependent Events

Probability is a ratio that predicts the likelihood an event will occur. Explore the concept of probability and understand the difference between independent and dependent events. Learn how to calculate the probability of both independent and dependent events, and review examples.

### 7. Factorial Practice Problems

Factorials are a process of multiplying a number by all previous integers smaller than itself. Learn how factorials appear as fractions and algebraic expressions and solve practice problems using multiplication and division.

### 8. What Is a Factorial?

Factorials are operations in which a given natural number is multiplied by all previous numbers in a sequence, typically all integers smaller than themselves. Learn the fundamental counting principles and how factorials calculate potential outcomes with two examples.

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

Factorials are used to compute for a combination. Learn more about these concepts, solve the example problems in this video using the combination discussed herein, and learn an easy technique for combination problems.

### 10. How to Calculate a Permutation

A permutation is a process for placing things into a linear order. Learn how to calculate a permutation. Explore factorials and permutation notations, and review examples of permutation calculations.

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

Independent events do not affect the outcome of events that follow, but it is generally important that they occur at least once. Learn how to use the 'At Least One' rule when calculating the probability of independent events.

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

Either/or probability of overlapping and non-overlapping events is determined by either adding the probability of each event occurring together or by subtracting out the probability of the overlapping event. Explore probability and overlapping vs. non-overlapping events.

### 13. Calculating the Standard Deviation

Standard deviation helps determine if a set of data is normally distributed by measuring how closely the data set surrounds the mean, or average. Learn about standard deviation, including the steps to calculate it. Explore variance, review examples of calculations, and understand what standard deviation means in regard to a data set.

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

Statistics often are expressed as percentages. Learn how to calculate percent increase using relative and cumulative frequency tables by exploring relative and cumulative frequencies, reviewing how to organize frequency data in a frequency table, and applying formulas to calculate percent increases.

### 15. How to Calculate Simple Conditional Probabilities

Conditional probability refers to the probability that an event will occur provided a previous event occurs. Learn about simple conditional probabilities and how to calculate them. Explore dependent events, understand how they differ from conditional probabilities, and review conditional probability examples.

### Earning College Credit

Did you know… We have over 220 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

### Other Chapters

Other chapters within the GRE Test: Practice & Study Guide course

- GRE: About the Test
- GRE Verbal Reasoning: About the Verbal Reasoning Section
- GRE Verbal Reasoning: Reading Skills
- GRE Verbal Reasoning: Vocabulary Skills
- GRE Analytical Writing: About the Analytical Writing Measure
- GRE Analytical Writing: Crafting Your Argument
- GRE Analytical Writing: Planning Your Essay
- GRE Analytical Writing: Starting Your Essay
- GRE Analytical Writing: Writing the Essay Body
- GRE Analytical Writing: Editing Your Essay
- GRE Analytical Writing: Writing Technique
- GRE Analytical Writing: Writing Stronger Sentences
- GRE Analytical Writing: Grammar and Usage
- GRE Quantitative Reasoning: About the Quantitative Reasoning Section
- GRE Quantitative Reasoning: Numbers and Operations
- GRE Quantitative Reasoning: Fractions, Decimals & Mixed Numbers
- GRE Quantitative Reasoning: Sequences and Series
- GRE Quantitative Reasoning: Equations and Expressions
- GRE Quantitative Reasoning: Factoring with FOIL, Graphing Parabolas and Solving Quadratics
- GRE Quantitative Reasoning: Exponents & Roots
- GRE Quantitative Reasoning: Functions
- GRE Quantitative Reasoning: Rational Equations and Expressions
- GRE Quantitative Reasoning: Inequalities
- GRE Quantitative Reasoning: Practical Applications
- GRE Quantitative Reasoning: Plane Geometry
- GRE Quantitative Reasoning: Coordinate Geometry
- GRE Quantitative Reasoning: Interpreting Statistical Data
- GRE Quantitative Reasoning: Sets
- GRE Flashcards
- GRE Test Flashcards
- GRE Test Essay Tips & Practice