Need help with Statistics, Probability, Combinatorics, or Charts & Graphs? You've come to the right place.

Volume 4 of Master Key to the GRE is the only guide to GRE math that will teach you everything you need to know about Statistics, Probability, Combinatorics, and Data Interpretation ("Charts & Graphs").

Whether you’re aiming for a perfect score or a score closer to average, mastery of the following concepts is essential.

- 1Introduction
- 2Averages
- 3Weighted Averages
- 4Medians & Modes
- 5Equally Spaced Number Sets
- 6Range, Quartiles, & Boxplots
- 7Standard Deviation
- 8Normal Distributions

The following concepts are either advanced or are tested only on rare occasions. If you don’t need an elite math score, don’t waste your time!

- 9Random Variables Peaks & Tails
- 10Maximization Problems
- 11The Weighted Average Shortcut
- 12Counting & Adding Equally Spaced Numbers

There’s no substitute for elbow grease. Practice your new skills to ensure that you internalize what you’ve studied.

- 13Problem Sets
- 14Solutions
- 15Video Solutions

Whether you’re aiming for a perfect score or a score closer to average, mastery of the following concepts is essential.

- 1Introduction
- 2Counting
- 3Factorials
- 4Permutations
- 5Duplicate Arrangements
- 6Combinations
- 7Separate Pools
- 8Summary

The following concepts are either advanced or are tested only on rare occasions. If you don’t need an elite math score, don’t waste your time!

- 9“Must Be Together” Problems Reverse Combinations
- 10Circular Arrangements
- 11“Fake Combinatorics” Questions
- 12Special Notation
- 13Slot Diagrams for Combinations

There’s no substitute for elbow grease. Practice your new skills to ensure that you internalize what you’ve studied.

- 14Problem Sets
- 15Solutions
- 16Video Solutions

Whether you’re aiming for a perfect score or a score closer to average, mastery of the following concepts is essential.

- 1Introduction
- 2The Probabilities Add to One
- 3From Zero to One
- 4Multiple Events
- 5“AND” Probabilities
- 6“OR” Probabilities
- 7Complements
- 8The “At Least Once” Shortcut
- 9Brute Force
- 10Summary

The following concepts are either advanced or are tested only on rare occasions. If you don’t need an elite math score, don’t waste your time!

- 11Unknown Relationships
- 12“Of Phrases”
- 13“At Least Twice or More”

There’s no substitute for elbow grease. Practice your new skills to ensure that you internalize what you’ve studied.

- 14Problem Sets
- 15Solutions
- 16Video Solutions

- 1Introduction
- 2Tackling the Questions
- 3Before Answering the Questions
- 4Approximation
- 5Digesting the Diagrams

Data Interpretation questions feature a variety of math concepts. You’ll find a proper review of those concepts here.

- 6Conversions
- 7Taking the Percent of a Number
- 8Percent Changes
- 9Percent Relationships
- 10Ratios, Averages & Medians
- 11Overlapping Sets
- 12Probability
- 13Math Drills

Familiarizing yourself with the graphs that you’ll encounter on the GRE, and the classic “traps” and “tricks” that come with them, is vital for mastering Data Interpretation questions.

- 14Bar Graphs
- 15Data Tables & Rare Diagrams
- 16Pie Charts
- 17Multi-Figure Data Sets
- 18Line Graphs

- 19Summary
- 20Problem Sets
- 21Solutions
- 22Video Solutions

For many programs, GRE scores are the most important metric for admission. They’re more important than your grade point average.

They’re more important than your work experience. They’re more important than your educational background. Isn’t an exam that means so much worth the cost of a college textbook? Of course it is.

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