In this hypothesis test, we are checking whether the mean delivery time is actually greater than 20 minutes, as opposed to the chain's claim of delivering within 20 minutes.

Step 1: State the null and alternative hypotheses

• The null hypothesis (H₀): The mean delivery time is 20 minutes, which aligns with the company's claim.

  $H_0: \mu = 20$

• The alternative hypothesis (Hₐ): The mean delivery time is greater than 20 minutes (since you are testing whether it's more than the claimed 20 minutes).

  $H_a: \mu > 20$

These hypotheses will be used for the hypothesis test.

Let me know if you'd like to proceed with the next step or need any clarification!

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Related Questions:

1. What kind of test statistic would be used in this scenario?
2. Why do we assume the population is normally distributed for this test?
3. How does the sample size affect the reliability of this hypothesis test?
4. What does the significance level of 0.005 imply in terms of rejecting the null hypothesis?
5. What are the possible outcomes of this hypothesis test?

Tip:

In hypothesis testing, if the p-value is less than the significance level, you reject the null hypothesis in favor of the alternative hypothesis.