AP Statistics
5A–5B Day 1 Exam Practice
Shared by Ashton · Oct 20, 2026 · 4 plays
Test-style questions on describing scatterplots, interpreting r, predictions, residuals, slope and intercept, extrapolation, outliers and changing units.
28 questions across 4 sections. After every answer you’ll see why each choice is right or wrong, not just the one you picked.
Sample questions
Open a question to see the answer choices and the correct answer.
An agronomist models corn yield (tons per acre) from rainfall (inches) for 20 fields with ŷ = 3.42 + 0.715x. Which is the correct interpretation of the slope?
- A. Each extra inch of rain causes 0.715 tons/acre more yield
- B. Predicted yield rises 0.715 tons/acre per extra inch of rain ✓
- C. Predicted rainfall rises 0.715 inches per extra ton of yield
- D. Yield rises exactly 0.715 tons/acre per extra inch of rain
Correct answer: B. Predicted + amount + per 1 unit of x + context. That's the slope frame.
An agronomist models corn yield (tons per acre) from rainfall (inches) for 20 fields with ŷ = 3.42 + 0.715x. One field got 12 inches of rain and yielded 13.1 tons/acre. What is its residual?
- A. +1.1 tons/acre ✓
- B. −1.1 tons/acre
- C. +0.1 tons/acre
- D. +12.0 tons/acre
Correct answer: A. Ŷ = 3.42 + 0.715(12) = 12.0. Residual = 13.1 − 12.0 = +1.1: this field yielded more than predicted.
An agronomist models corn yield (tons per acre) from rainfall (inches) for 20 fields with ŷ = 3.42 + 0.715x. What does the y intercept (3.42) mean here, if anything?
- A. Predicted yield with 0 inches of rain, if 0 is near the data ✓
- B. The predicted yield at the average rainfall
- C. The yield increase for each additional inch of rainfall
- D. The average yield for all 20 fields in the study
Correct answer: A. It's the predicted y at x = 0, and it's only meaningful if 0 inches is a realistic value close to the data.
For 2001–2020, the correlation between year and North Dakota oil production is r = 0.943. A student says this proves a strong linear relationship. What's the best response?
- A. No, since r would need to be exactly 1 for linear
- B. No, since year can't be used as a variable here
- C. Not necessarily; a curved pattern can also have r near 1 ✓
- D. Yes, since any r above 0.9 shows a linear pattern
Correct answer: C. This is the slides' Alternate Example 2. The scatterplot of the oil data is clearly curved.
Across 50 cities, the number of police officers and the number of crimes have r = 0.88. Which is the most reasonable explanation?
- A. The correlation must be a mistake in the calculation
- B. A lurking variable, city population, drives both counts ✓
- C. More crime causes cities to need fewer police officers
- D. Hiring more police officers causes crime to increase
Correct answer: B. Bigger cities have more of both. Correlation doesn't imply causation.