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## High school statistics

### Course: High school statistics>Unit 5

Lesson 5: Inference and experiments

# Conclusions in observational studies versus experiments

AP.STATS: DAT‑2 (EU), DAT‑2.A (LO), DAT‑2.A.3 (EK), DAT‑2.A.4 (EK), DAT‑2.B (LO), DAT‑2.B.3 (EK), VAR‑3 (EU), VAR‑3.E (LO), VAR‑3.E.2 (EK), VAR‑3.E.3 (EK) CCSS.Math: HSS.IC.B

## Problem

The superintendent of a large school district is curious about the relationship between students' grades and their participation in extracurricular activities. They take a random sample of 500 students and find that students with more participation in extracurricular activities are far more likely to have high grades than students with little or no participation.
What conclusion can they draw from this study?