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AP Statistics / Unit 4

Unit 4 · 10–20%

Inference for Quantitative Data: Means

Estimate and test population means when the data are measurements.

Start first lessonUnit practice

Topics

  • Sampling distributions for a mean
  • t-intervals for one mean
  • t-tests for one mean
  • Comparing two means
  • Paired data versus two groups

Lessons

Key terms

Original practice

Marlow Works questions. If this unit does not have its own items yet, you will see other questions from the same course.

1 of 3Exploring One-Variable Data and Collecting Data · easy · multiple choice

A reporter stands at one grocery-store exit and asks shoppers whether they support a new park tax. Why is this a poor way to estimate citywide support?

Original Marlow Works item — not a College Board question.

Take your time—this is practice, not a test.

Review checklist

  1. 01Decide whether you have one sample, two samples, or pairs.
  2. 02Check plots for skew and outliers before trusting a small-sample t procedure.
  3. 03Interpret the interval or test for the mean, not for every individual value.

Related resources

External links with reuse status. Marlow Works is independent and does not copy restricted exam or textbook material.

  • Official / link only

    AP Statistics course page

    Official revised 2026–27 five-unit framework.

    College Board · All rights reserved · accessed 2026-10-01

    Open source

  • CC BY — attribution required

    Collaborative Statistics

    Open statistics text for distributions, probability, and inference.

    Open Textbook Library listing · CC BY · accessed 2026-10-01

    Open source