AP Statistics · Topic 7.10
Skills Focus: Selecting, Implementing, and Communicating Inference Procedures Practice
Part of Inference for Quantitative Data: Means.
Practice questions
5
Sample questions
5 of 5 — sign in to practice the rest with adaptive difficulty and mastery tracking.
Sample 1difficulty 3/5
A CI procedure with 95% confidence captures the parameter
- Acheck_circle
About 95% of the time in repeated sampling
- B
Always
- C
Only if H₀ is true
- D
Never if biased
Why
Frequentist guarantee: 95% of intervals capture the true parameter in the long run.
- A
Sample 2difficulty 3/5
Use z (not t) when
- A
Always
- B
n < 30 always
- Ccheck_circle
σ is known
- D
σ is unknown
Why
Most real cases use t because σ is rarely known.
- A
Sample 3difficulty 4/5
Use a paired t when data are
- A
Categorical
- Bcheck_circle
Pairs of related observations (matched/repeated)
- C
Two unrelated samples
- D
One sample only
Why
Pairing reduces variability by controlling for individual differences.
- A
Sample 4difficulty 4/5
Comparing the same group's heart rate before and after exercise uses
- A
Two-sample t
- B
Chi-square
- Ccheck_circle
Paired t (matched)
- D
Two-sample z
Why
Same individuals measured twice → paired/matched.
- A
Sample 5difficulty 4/5
A 95% CI for μ that excludes 0 implies
- A
Always fails to reject
- Bcheck_circle
Two-sided test of H₀: μ = 0 rejects at α = 0.05
- C
Sample bias
- D
p-value > 0.05
Why
CI exclude null value ⇔ test rejects at the corresponding level.
- A