Question 35

A professor in the Accountancy Department of a business school indicated that there is much more variability in the final exam scores of students taking the introductory accounting course as a requirement than for students taking the course as part of their major. Random samples of 16 non-accounting majors and 10 accounting majors taken from the professor's class roster in his large lecture and the following results are computed based on the final exam scores:

Non-Accounting Major (1) Accounting Major (2)

n=16 n=10

S²= 210.2 S²= 36.5

Using=5%, the test and critical F-values, for the hypothesis test to support the professor's statement, respectively are:

Select one:

a. 5.7589 and 3.77 respectively

b. 0.1736 and 3.77 respectively

c. 5.7589 and 3.01 respectively

d. 2.3998 and 3.01 respectively

Question 42

An electrical engineer is interested in the effect on the tube conductivity of five different types of coating for cathode ray tubes used in telecommunications system display device. The following conductivity data are obtained:

Coating Type

1143141150146

2152149137143

3134133132127

4129127132129

5147148144142

At 5% level of significance, is there any difference in conductivity due to coating type? What is the value of test statistic?

Select one:

a. 16.35

b. 19.0

c. 15

d. 3.06

Question 43

Last school year, the student body of a local university consisted of 30% freshmen, 24% sophomores, 26% juniors, and 20% seniors. A sample of 400 students taken from this year's student body showed the following number of students in each classification.

Freshmen 113 Sophomores 98 Juniors 115 Seniors 74

We are interested in determining whether or not there has been a significant change in the classifications between the last school year and this school year. The calculated value for the test statistic equals

Select one:

a. .54.

b. .65.

c. 2.063.

d. 2.664.

Question 46

An electric company operates a fleet of trucks that provide electrical service to the construction industry. Monthly maintenance cost has been $75 per truck. A random sample of 16 trucks provided a sample mean maintenance cost of $82.50 per month, with a sample standard deviation of $30. Using a 5% level of significance, you like to see whether the mean monthly maintenance cost has increased. Set the appropriate hypotheses and calculate the test statistic

Select one:

a. Z = +/- 1.0

b. t = +/-1.0

c. Z = 1.0

d. t = 1.0