Problem 1: The null and alternate hypotheses are:
Ho: μ1 < μ2
H1: μ1 > μ2
A random sample of 20 items from the first population showed a mean of 100 and a standard deviation of 15. A sample of 16 items for the second population showed a mean of 94 and a standard deviation of 8. Use the .05 significant levels.
Problem 2: An investigation of the effectiveness of an antibacterial soap in reducing operating room contamination resulted in the accompanying table. The new soap was tested in a sample of eight operating rooms in the greater Seattle area during the last year. The following table reports the contamination levels before and after the use of the soap for each operating room.=
Operating Room
A B C D E F G H
Before 6.6 6.5 9 10.3 11.2 8.1 6.3 11.6
After 6.8 2.4 7.4 8.5 8.1 6.1 3.4 2
At the .05 significance level, can we conclude the contamination measurements are lower after use of the new soap?
Problem 3: Refer to the Lincolnville School District bus data. Is there a difference in the mean maintenance cost for the diesel versus the gasoline buses? Use the .05 significance level.
CASES - A. Century National Bank
Mr. Selig is also interested in the bank's ATMs. Is there a difference in ATM use among the branches? Also, do customers who have debit cards tend to use ATMs differently from those who do not have debit cards? Is there a difference in ATM use by those with checking accounts that pay interest versus those that do not? Prepare a report for Mr. Selig answering these questions.
|
Date
|
Day
|
Patients
|
|
9-29-16
|
Monday
|
38
|
|
9-30-16
|
Tuesday
|
28
|
|
10-01-16
|
Wednesday
|
28
|
|
10-02-16
|
Thursday
|
30
|
|
10-03-16
|
Friday
|
35
|
|
10-06-16
|
Monday
|
35
|
|
10-07-16
|
Tuesday
|
25
|
|
10-08-16
|
Wednesday
|
22
|
|
10-09-16
|
Thursday
|
21
|
|
10-10-16
|
Friday
|
32
|
|
10-13-16
|
Monday
|
37
|
|
10-14-16
|
Tuesday
|
29
|
|
10-15-16
|
Wednesday
|
27
|
|
10-16-16
|
Thursday
|
28
|
|
10-17-16
|
Friday
|
35
|
|
10-20-16
|
Monday
|
37
|
|
10-21-16
|
Tuesday
|
26
|
|
10-22-16
|
Wednesday
|
28
|
|
10-23-16
|
Thursday
|
23
|
|
10-24-16
|
Friday
|
33
|
Attachment:- Practice Problems.rar