Question 1
Management of a hotel was concerned with increasing return rate for hotel guests. One aspect of first impressions y guests relates to the time it takes to deliver the guest's luggage to the room after check-in to the hotel. A random sample of 20 deliveries on a particular day were selected in Wing A of the hotel and a random sample of 20 deliveries were selected in Wing B. Analyze the data and determine whether there is a difference in the mean delivery time in the two wings of the hotel (use a = 0.05).
|
Wing A
|
Wing B
|
|
10.70
|
7.20
|
|
9.89
|
6.68
|
|
11.83
|
9.29
|
|
9.04
|
8.95
|
|
9.37
|
6.61
|
|
11.68
|
8.53
|
|
8.36
|
8.92
|
|
9.76
|
7.95
|
|
13.67
|
7.57
|
|
8.96
|
6.38
|
|
9.51
|
8.89
|
|
10.85
|
10.03
|
|
10.57
|
9.30
|
|
11.06
|
5.28
|
|
8.91
|
9.23
|
|
11.79
|
9.25
|
|
10.59
|
8.44
|
|
9.13
|
6.57
|
|
12.37
|
10.61
|
|
9.91
|
6.77
|
Question 2
The manager of computer operations of a large company wants to study computer usage of two departments within the company, namely the accounting department and the research department. A random sample of five jobs from the accounting and six jobs from the research department in the past week was selected and the processing time (in minutes) for each job was recorded as follows:
|
Department
|
Processing Time (in minutes)
|
|
Accounting
|
9
|
3
|
8
|
7
|
12
|
|
|
Research
|
4
|
13
|
10
|
9
|
9
|
6
|
a) Determine the proportion of jobs, which take more than 10 minutes for both samples.
b) Is there evidence of a significant difference between the accounting department and the research department with regards to the proportion of jobs, which take more than 10 minutes? Use a 5% significance level.
c) What is the p-value for the above test?
Question 3
The weekly wage amounts, in RM of the random sample of 15 employees who do have an overtime payment are given in the following table.
|
70
|
166
|
140
|
151
|
133
|
|
200
|
200
|
118
|
132
|
125
|
|
165
|
137
|
210
|
137
|
140
|
a) Determine the unbiased point estimates of the mean and the standard deviation for the above sample. [Round your answer to two decimal places.]
b) The weekly wage of the sample of 75 employees who do not have an overtime payment have a mean of 140 and a standard deviation of 32. At the 5% level of significance, is there evidence that the weekly wage of employees who have overtime is earning more than those who don't have overtime?