AP Statistics · Exam guide
AP Statistics Multiple-Choice Guide: 42 Questions and How to Choose
The multiple-choice section of the AP Statistics exam has 42 questions, and together with the four free-response questions it makes up the whole exam score. Most questions are conceptual: they ask what a result means, which method fits, or which conclusion is justified. This guide shows the question types and the habits that remove wrong answers quickly.
The format
- 42 multiple-choice questions, followed by 4 free-response questions. Each section is half of the exam score.
- A calculator is allowed. A formula and table sheet is provided.
- There is no penalty for a wrong answer, so answer every question.
The question types
| Type | What to do |
|---|---|
| Choose the procedure | Decide from the context: one or two groups, means or proportions, paired or independent, categorical or quantitative. |
| Interpret a result | Say what a number means in the words of the context: a confidence level, a p-value, a slope, a standard deviation. |
| Conditions | Decide whether random sampling, independence (the 10 percent rule), and large-sample conditions hold. |
| Compute | Use the formula or the calculator, and check that the answer is reasonable. |
| Design | Decide whether a study is an observational study or an experiment, and what the conclusion can be. |
A worked example
A 95 percent confidence interval for the mean weight gain of cattle on a new feed is \(8.2\) to \(11.6\) pounds. Which is the best interpretation?
Options: A. 95 percent of cattle gained between 8.2 and 11.6 pounds. B. We are 95 percent confident that the mean weight gain on the new feed is between 8.2 and 11.6 pounds. C. There is a 95 percent probability that the sample mean is between 8.2 and 11.6. D. 95 percent of all samples have a mean between 8.2 and 11.6.
The answer is B. A is about individual cattle, but the interval is for the mean. C treats the sample mean as the unknown, but the sample mean is known and is in the center of the interval. D is about the sampling process, not this interval.
Traps that appear again and again
- Confusing the sample and the population: a statistic describes a sample, a parameter describes a population.
- Treating a p-value as the probability that the null hypothesis is true.
- Concluding cause and effect from an observational study.
- Saying "accept the null hypothesis" instead of "fail to reject."
- Confusing a confidence level with the probability that a particular interval is right.
Common mistakes
- Skipping the conditions of a procedure.
- Choosing an answer because the number matches, without checking the context.
- Reading too fast over words such as "at least" or "more than."
- Leaving a question blank.
Frequently asked questions
Is there a penalty for guessing?
No. Answer every question.
Can I use a calculator on the multiple-choice section?
Yes. A calculator is allowed on the whole exam, and a formula and table sheet is provided.
How many questions are free response?
Four, which together count for half the exam score.
What does a p-value mean?
It is the probability, assuming the null hypothesis is true, of getting a result at least as extreme as the one observed.
Where can I find the official format?
Exam formats change a little from year to year, so check the current course and exam description on the College Board site before test day.
Keep practicing
Every lesson in the AP Statistics course ends with practice problems and an Exam focus box that shows how the topic is tested, and every unit has a 10-problem practice set with worked answers. These free lessons also build the skills the free-response section tests:
See the AP Statistics course Free lessons and lesson list
More AP Statistics guides (8)
Start here
Free-response and writing
- AP Statistics Inference for Proportions Explained: Intervals and Tests with a Worked Example
- AP Statistics Inference for Means Explained: The One-Sample t Test and Checking Conditions
- AP Statistics Chi-Square Test Explained: Homogeneity and Independence with a Worked Example
- AP Statistics Regression Questions Explained: Interpreting Slope, r-Squared and Residuals
- AP Statistics Describing Data: Shape, Center, Spread, and Outliers in Context
- AP Statistics Sampling and Experiments: Bias, Random Samples, and Good Design
- AP Statistics Probability and Random Variables: Expected Value, Binomial, and Normal
AP is a registered trademark of the College Board, which is not affiliated with and does not endorse this site. This guide is our own explanation of the question types and scoring. For the official scoring guidelines, see the College Board.