AP Statistics
AP Stats Unit 1 Part 2 (1F 1H) Super Hard MCQ 2
Shared by ashtont · Oct 7, 2026 · 1 play
36 questions across 3 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 experiment on seedling growth uses 3 temperatures and 4 humidity settings, with every combination used on the same number of trays. There are 96 trays of seedlings. How many treatments are there, and how many trays receive each one?
- A. 7 treatments, with about 14 trays each
- B. 12 treatments, with 8 trays each ✓
- C. 2 treatments, with 48 trays each
- D. 12 treatments, with 96 trays each
Correct answer: B. Treatments are the combinations of the levels of the two factors: 3 x 4 = 12. Then 96 / 12 = 8 trays per treatment.
A study finds that people who visit the coast often tend to report better health than people who never visit. A student says income is a confounding variable. Which explanation correctly justifies that claim?
- A. People with higher incomes tend to have better health because they can afford better care and food.
- B. People with higher incomes can more easily afford trips to the coast.
- C. People who visit the coast are healthier, so income must be the reason.
- D. People with higher incomes can more easily afford trips to the coast, and people with higher incomes also tend to have better health because they can afford better care and food. ✓
Correct answer: D. To show confounding, the variable must be linked to the explanatory variable (coast visits) and also to the response (health). This explanation gives both links.
A store randomly selects 200 customers from its loyalty-program list, then randomly assigns each to receive a 10% coupon or a free-shipping offer. Those sent free shipping spend significantly more. What conclusion is appropriate?
- A. Free shipping causes higher spending than the coupon, for all customers in the store's loyalty program. ✓
- B. Free shipping causes higher spending than the coupon, but only for these 200 customers.
- C. Free shipping is associated with higher spending for loyalty members, but cause and effect cannot be concluded.
- D. Free shipping causes higher spending than the coupon, for all of the store's customers.
Correct answer: A. Random assignment with a significant difference supports cause and effect, and random selection from the list supports generalizing to everyone on it.
Psychology students at one university volunteer for a study and are randomly assigned to study with music or in silence. The silence group scores significantly higher on a memory test. What is the largest group the result can be applied to?
- A. All students at that university
- B. All college students
- C. Students similar to the ones who volunteered ✓
- D. Nobody, because the subjects were volunteers
Correct answer: C. The subjects were volunteers, not a random sample, so the result applies only to individuals like those in the study.
A national health survey asks a random sample of adults whether they have a college degree and whether they had symptoms of depression in the past year. Symptoms were more common among adults without a degree. Which statement is correct?
- A. This is an experiment, because two groups were compared.
- B. This is an observational study, so it shows an association among U.S. adults but not that earning a degree lowers the chance of depression. ✓
- C. This shows that earning a degree lowers the chance of depression, because the sample was random.
- D. This is an observational study, so nothing can be said beyond the adults who were surveyed.
Correct answer: B. A survey is an observational study: nothing was assigned. The random sample supports generalizing to the population sampled, but not cause and effect.