Question

The manager of a grocery store has taken a random sample of 100 customers. The average length of time it took the customers in the sample to check out was 3.2 minutes with a standard deviation of 0.5 minutes. We want to test to determine whether or not the mean waiting time of all customers is any different from 3 minutes (use the significance level 0.05 for the test).

Round your solutions for this Exhibit to 4 decimal places.

A.) Refer to the Exhibit Check Out Times.
Provide the null and the alternative hypotheses.
Group of answer choices
a. H0:μ≠3;H1:μ=3
b. H0:μ=3;H1:μ≠3
c. H0:μ=3.1;H1:μ≠3.1
d. H0:μ≠3.1;H1:μ=3.1

Answer 1

The correct null and alternative hypotheses for testing if the mean waiting time is different from 3 minutes are H0: μ = 3 and H1: μ ≠ 3.

Step-by-step explanation:

The manager of a grocery store is testing to determine whether the mean waiting time for checkout is different from 3 minutes. Given a sample mean of 3.2 minutes, a sample standard deviation of 0.5 minutes, and a sample size of 100 customers, the appropriate null and alternative hypotheses for a two-tailed test at a significance level of 0.05 would be:

• H0: μ = 3, which states that the mean waiting time is 3 minutes.
• H1: μ ≠ 3, which states that the mean waiting time is not equal to 3 minutes.

Hence, the correct answer is: b. H0: μ = 3; H1: μ ≠ 3.