Sample Exam I Questions

MSC 287

Dr. Lovelace

 

3.     financial analyst is interested in the amount of resources spent by computer hardware and software companies on research and development (R&D).  She sapmles 50 of these high-technology firms and calculates the amount each spent last year on R&D as a percentage of their total revenues.  The results are given below.

 

 

 

13.5

8.0

8.2

9.6

7.1

8.4

7.9

8.0

7.2

13.2

10.5

6.8

7.7

8.8

7.7

9.0

9.5

7.4

11.3

5.9

9.2

8.1

6.5

8.5

5.2

9.7

13.5

9.5

9.4

5.6

6.6

9.9

8.2

10.5

11.7

10.6

6.9

6.9

6.9

6.0

10.1

7.5

7.2

6.5

7.8

7.1

11.1

8.2

7.5

6.5

 

     For a frequency distribution of this data,

 

a.      How many classes would you suggest?   (5 pts.)

 

 

 

b.     What would be the lower limit of the lowest class?   (10 pts.)

 

 

 

c.      What would be the upper limit of the highest class?   (10 pts.)

 

 

 

d.     What would be the class width?    (10 pts.)

 

 

e.      Construct a frequency distribution.

 

 

 

 

 

 

 

3.  The Midland National Bank selected a sample of 40 student checking accounts.  Below are their end-of-month balances.  (The data have already been put in order from smallest to largest for your test-taking pleasure and convenience).

 

27

57

87

141

215

279

327

425

503

712

37

68

123

149

234

302

350

440

521

758

43

72

125

185

234

303

358

489

608

863

55

74

127

203

252

321

404

489

703

968

 

 

(a) Determine the first quartile (i.e., the 25th percentile) of the bank balance data.  (10 pts.)

 

 

 

 

4.  Your height and weight are examples of which level of measurement?  (5 pts.)

 

a.   Nominal

b.   Ordinal

c.   Interval

d.   Ratio

e.   none of the above

 

 

 

 

 

 

 

5.  Shoe sizes, such as 7B, 10D, and 12EEE, are examples of what level of measurement?    (5 pts.)

 

a.   Nominal

b.   Ordinal

c.   Interval

d.   Ratio

e.   none of the above

 

 

 

 

1.   The U.S. Department of Education reported that for the past six years 23, 19, 15, 30, 27, and 25 women per year received doctorate degrees in computer and information sciences. 

 

(a) Find the arithmetic mean number of women per year receiving these degrees.  (5 pts.)

 

 

 

 

 

 

(b)  Find the standard deviation of this data.  (10 pts.)

 

 

 

 

 

1.   Give an example of data whose point of central tendency is best described by the median, not the mean.  (Example:  home selling price).  Tell why the median is superior to the mean in your particular example.  (10 pts.)

 

 

 

 

 

 

2.   For each of the following, determine whether the group is a sample or a population. 

 

a.   The 30 stocks reported as a part of the Dow Jones Industrial Average.  (2.5 pts.)

 

b.  All those incarcerated in the Limestone County Jail.  (2.5 pts.)

 

c.   The ACT scores of the freshmen class at Auburn University. 

               (2.5 pts.)

 

d.   The participants in a study of a new cholesterol drug.  (2.5

                 (2.5 pts.)