You may need to use the appropriate technology to answer this question. Joan's Nursery specializes in custom-designed landscaping for residential areas. The estimated labor cost associated with a particular landscaping proposal is based on the number of plantings of trees, shrubs, and so on to be used for the project. For cost-estimating purposes, managers use two hours of labor time for the planting of a medium-sized tree. Actual times from a sample of 10 plantings during the past month follow (times in hours). 1.6 1.4 2.7 2.3 2.5 2.3 2.6 3.0 1.3 2.3 With a 0.05 level of significance, test to see whether the mean tree-planting time differs from two hours. (a) State the null and alternative hypotheses.

H0: 𝜇 = 2 Ha: 𝜇 ≠ 2

H0: 𝜇 ≤ 2 Ha: 𝜇 > 2

H0: 𝜇 > 2 Ha: 𝜇 ≤ 2

H0: 𝜇 < 2 Ha: 𝜇 ≥ 2

H0: 𝜇 ≥ 2 Ha: 𝜇 < 2 Correct: Your answer is correct. (b) Compute the sample mean. 2.20

Correct: Your answer is correct. (c) Compute the sample standard deviation. (Round your answer to three decimal places.) 0.613

Incorrect: Your answer is incorrect. (d) What is the test statistic? (Round your answer to three decimal places.) 1.164

Incorrect: Your answer is incorrect. What is the p-value? (Round your answer to four decimal places.) p-value = 0.274

Incorrect: Your answer is incorrect. (e) What is your conclusion?

Do not reject H0. We cannot conclude that the mean tree-planting time differs from two hours. There is no reason to change from the two hours for cost estimating purposes. Reject H0. We can conclude that the mean tree-planting time differs from two hours. There is a reason to change from the two hours for cost estimating purposes.
Do not reject H0. We can conclude that the mean tree-planting time differs from two hours. There is a reason to change from the two hours for cost estimating purposes. Reject H0. We cannot conclude that the mean tree-planting time differs from two hours. There is no reason to change from the two hours for cost estimating purposes.