📊AP Statistics Review

AP Statistics covers 9 units, from Exploring One–Variable Data to Slopes. Review each unit with study guides, practice questions, and key terms — compiled by AP educators and updated for the 2027 AP exam.

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AP Statistics Exam →

Multiple-Choice Questions (MCQ)

FRQs 1-5 – Free Response

FRQ 6 – Investigative Task

Unit 1 – Exploring One–Variable Data →

1.1

Introducing Statistics: What Can We Learn from Data?

1.2

The Language of Variation: Variables

1.3

Representing a Categorical Variable with Tables

1.4

Representing a Categorical Variable with Graphs

1.5

Representing a Quantitative Variable with Graphs

1.6

Describing the Distribution of a Quantitative Variable

1.7

Summary Statistics for a Quantitative Variable

1.8

Graphical Representations of Summary Statistics

1.9

Comparing Distributions of a Quantitative Variable

1.10

The Normal Distribution

Unit 2 – Exploring Two–Variable Data →

2.1

Introducing Statistics: Are Variables Related?

2.2

Representing Two Categorical Variables

2.3

Statistics for Two Categorical Variables

2.4

Representing the Relationship Between Two Quantitative Variables

2.5

Correlation

2.6

Linear Regression Models

2.7

Residuals

2.8

Least Squares Regression

2.9

Analyzing Departures from Linearity

Unit 3 – Collecting Data →

3.1

Introducing Statistics: Do the Data We Collected Tell the Truth?

3.2

Introduction to Planning a Study

3.3

Random Sampling and Data Collection

3.4

Potential Problems with Sampling

3.5

Introduction to Experimental Design

3.6

Selecting an Experimental Design

3.7

Inference and Experiments

Unit 4 – Probability, Random Variables, and Probability Distributions →

4.1

Introducing Statistics: Random and Non-Random Patterns?

4.2

Estimating Probabilities Using Simulation

4.3

Introduction to Probability

4.4

Mutually Exclusive Events

4.5

Conditional Probability

4.6

Independent Events and Unions of Events

4.7

Introduction to Random Variables and Probability Distributions

4.8

Mean and Standard Deviation of Random Variables

4.9

Combining Random Variables

4.10

Introduction to the Binomial Distribution

4.11

Parameters for a Binomial Distribution

4.12

The Geometric Distribution

Unit 5 – Sampling Distributions →

5.1

Introducing Statistics: Why Is My Sample Not Like Yours?

5.2

The Normal Distribution, Revisited

5.3

The Central Limit Theorem

5.4

Biased and Unbiased Point Estimates

5.5

Sampling Distributions for Sample Proportions

5.6

Sampling Distributions for Differences in Sample Proportions

5.7

Sampling Distributions for Sample Means

5.8

Sampling Distributions for Differences in Sample Means

Unit 6 – Proportions →

6.1

Introducing Statistics: Why Be Normal?

6.2

Constructing a Confidence Interval for a Population Proportion

6.3

Justifying a Claim Based on a Confidence Interval for a Population Proportion

6.4

Setting Up a Test for a Population Proportion

6.5

Interpreting p-Values

6.6

Concluding a Test for a Population Proportion

6.7

Potential Errors When Performing Tests

6.8

Confidence Intervals for the Difference of Two Proportions

6.9

Justifying a Claim Based on a Confidence Interval for a Difference of Population Proportions

6.10

Setting Up a Test for the Difference of Two Population Proportions

6.11

Carrying Out a Test for the Difference of Two Population Proportions

Unit 7 – Means →

7.1

Introducing Statistics: Should I Worry About Error?

7.2

Constructing a Confidence Interval for a Population Mean

7.3

Justifying a Claim About a Population Mean Based on a Confidence Interval

7.4

Setting Up a Test for a Population Mean

7.5

Carrying Out a Test for a Population Mean

7.6

Confidence Intervals for the Difference of Two Means

7.7

Justifying a Claim About the Difference of Two Means Based on a Confidence Interval

7.8

Setting Up a Test for the Difference of Two Population Means

7.9

Carrying Out a Test for the Difference of Two Population Means

7.10

Skills Focus: Selecting, Implementing, and Communicating Inference Procedures

Unit 8 – Chi–Squares →

8.1

Introducing Statistics: Are My Results Unexpected?

8.2

Setting Up a Chi Square Goodness of Fit Test

8.3

Carrying Out a Chi Square Goodness of Fit Test

8.4

Expected Counts in Two Way Tables

8.5

Setting Up a Chi-Square Test for Homogeneity or Independence

8.6

Carrying Out a Chi-Square Test for Homogeneity or Independence

8.7

Skills Focus: Selecting an Appropriate Inference Procedure for Categorical Data

Unit 9 – Slopes →

9.1

Introducing Statistics: Do Those Points Align?

9.2

Confidence Intervals for the Slope of a Regression Model

9.3

Justifying a Claim About the Slope of a Regression Model Based on a Confidence Interval

9.4

Setting Up a Test for the Slope of a Regression Model

9.5

Carrying Out a Test for the Slope of a Regression Model

9.6

Skills Focus: Selecting an Appropriate Inference Procedure

Frequently Asked Questions →

What is bias?

Exam Skills →

Score Higher on AP Statistics: FRQ Tips from Students

AP Stats Mixed Units Practice FRQ #4 & Feedback

AP Stats Unit 7 FRQ Practice Prompt (#1) Answers & Feedback

AP Stats Unit 1 Practice FRQ Prompt Answers & Feedback

AP Stats Mixed Units Practice FRQ #3 & Feedback

AP Stats Mixed Units Practice FRQ #2 & Feedback

AP Stats Unit 4 FRQ Practice Prompt Answers & Feedback

AP Stats Unit 4 Practice FRQ #2

AP Stats FRQ Practice Prompt Answers & Feedback (Unit 2)

AP Stats Mixed Units Practice FRQ #1 & Feedback

AP Stats FRQ Practice Prompt Samples & Feedback (Unit 5)

AP Stats Practice FRQ Responses & Feedback (Unit 6)

AP Stats Practice FRQ Responses & Feedback (Unit 4)

AP Stats Unit 3 FRQ Practice Prompt Answers & Feedback

AP Statistics teaches you to collect, explore, and reason about real-world data, then build formal inference like confidence intervals and hypothesis tests while clearly justifying every conclusion.

Frequently Asked Questions

What does AP Statistics cover?

AP Statistics covers data analysis, sampling and experimental design, probability, random variables, inference, and statistical reasoning.

How should I use these AP Stats study guides?

Use the unit guides to review each major concept, then work through AP-style practice to strengthen interpretation, setup, and calculator-supported reasoning.

Where can I find AP Statistics FRQ practice?

Fiveable's AP Statistics FRQ practice includes AP-style free-response questions with AI-supported scoring so you can practice showing work, explaining conditions, and interpreting results.

What should I review first in AP Stats?

Start with the units where you lose points most often, especially inference or probability. For exam review, focus on describing the setup clearly before worrying about every calculation detail.

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