LEARN · EXPLAIN · REVISE

An anonymous commute survey records 20k students; 12k travel at most 30 minutes. Find the sample proportion.

Read the idea, work independently, then explain what changed.

高一必修第二册(A版).pdf · 9.3 · PDF 227 / printed page 220

TOPIC 01

Statistical case study

Build understanding of statistical case study through definitions, contrasting cases and justified applications.

Use one hint at a time. A correction explains what changed, not just the final answer.

01 / Foundation#Your turn

k=3

Skills and prerequisite lessons

Working and explanation

BUILD THE REASONING

Hint 1

State the survey question, population, sampling and measurement rules before drawing a conclusion.

Hint 2

Count the students meeting the stated inclusive threshold.

Worked solution

State the survey question, population, sampling and measurement rules before drawing a conclusion.
Calculate or simplify this relation.
$\hat p=36/60=0.6$
The measured outcome is duration, not distance.

The requested value is 0.6.

Checks and common pitfalls: The measured outcome is duration, not distance.

Think first. Reveal a hint when the class is ready.

Teacher preparation and assessment

Use statistical case study to state a justified conclusion.
Full investigation: Define the target, collect compatible data, analyze and report limitations.
Ethical reporting: Use anonymous classroom data and preserve uncertainty and exclusions.
Close with: conditions → representation → reasoning → check.

Expected reasoning: Define the target, collect compatible data, analyze and report limitations.
Expected reasoning: Use anonymous classroom data and preserve uncertainty and exclusions.
Expected correction: A statistical association alone is not a causal conclusion.