AP Statistics / Unit 4: Inference for Quantitative Data: Means

4.8 Justifying a Claim Based on a Confidence Interval for the Difference Between Two Population Means

3 practice questions

Notes

Interval contains 0: no difference is plausible.
Entirely above 0: evidence $\mu_1>\mu_2$. Entirely below: $\mu_1<\mu_2$.

Practice

A 95% CI for $\mu_1-\mu_2$ is $(-5.2, 1.1)$. This means:

A CI of $(2.1, 6.8)$ for $\mu_A-\mu_B$ suggests:

A CI that includes 0 proves the means are equal:

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