# MATHEMATICS

1) Those methods involving the collection, presentation, and characterization of a set of data in order to properly describe the various features of that set of data are called

A) statistical inference.

B) the scientific method.

C) sampling.

D) descriptive statistics.

Answer: D

2) Which of the following is NOT an element of descriptive statistical problems?

A) an inference made about the population based on the sample

B) the population or sample of interest

C) tables, graphs, or numerical summary tools

D) identification of patterns in the data

Answer: A

3) Most analysts focus on the cost of tuition as the way to measure the cost of a college education. But incidentals, such as textbook costs, are rarely considered. A researcher at Drummand University wanted to estimate the textbook costs of first-year students at Drummand. To do so, she monitored the textbook cost of 250 first-year students and found that their average textbook cost was $600 per semester. Identify the population of interest to the researcher.

A) all Drummand University students

B) all college students

C) all first-year Drummand University students

D) the 250 students that were monitored

Answer: C

4) Researchers are concerned that the weight of the average American school child is increasing, implying, among other things, that children’s clothing should be manufactured and marketed in larger sizes. If *X* is the weight of school children sampled in a nationwide study, then *X* is an example of

A) a categorical random variable.

B) a discrete random variable.

C) a continuous random variable.

D) a parameter.

Answer: C

5) The chancellor of a major university was concerned about alcohol abuse on her campus and wanted to find out the proportion of students at her university who visited campus bars on the weekend before the final exam week. Her assistant took a random sample of 250 students. The answer on “whether you visited campus bars on the weekend before the final exam week” from students in the sample is an example of

A) a categorical random variable.

B) a discrete random variable.

C) a continuous random variable.

D) a parameter.

Answer: A

6) The British Airways Internet site provides a questionnaire instrument that can be answered electronically. Which of the four methods of data collection is involved when people complete the questionnaire?

A) published sources

B) experimentation

C) surveying

D) observation

Answer: C

7) A professor of economics at a small Texas university wanted to determine what year in school students were taking his tough economics course. Shown below is a pie chart of the results. What percentage of the class took the course prior to reaching their senior year?

A) 14%

B) 44%

C) 54%

D) 86%

Answer: D

8) One of the developing countries is experiencing a baby boom, with the number of births rising for the fifth year in a row, according to a BBC News report. Which of the following is best for displaying this data?

A) a Pareto chart

B) a two-way classification table

C) a histogram

D) a time-series plot

Answer: D

9) In a survey, 150 executives were asked what they think is the most common mistake candidates make during job interviews. Six different mistakes were given. Which of the following is the best for presenting the information?

A) a bar chart

B) a histogram

C) a stem-and-leaf display

D) a contingency table

Answer: A

The ordered array below resulted from selecting a sample of 25 batches of 500 computer chips and determining how many in each batch were defective.

Defects

1 2 4 4 5 5 6 7 9 9 12 12 15

17 20 21 23 23 25 26 27 27 28 29 29

10) Referring to the table above, if a frequency distribution for the defects data is constructed, using “0 but less than 5” as the first class, the frequency of the “20 but less than 25” class would be ________.

Answer: 4

11) Referring to the table above, if a frequency distribution for the defects data is constructed, using “0 but less than 5” as the first class, the relative frequency of the “15 but less than 20” class would be ________.

12) Which of the following statistics is NOT a measure of central tendency?

A) arithmetic mean

B) median

C) mode

D) *Q*3

Answer: D

13) Which descriptive summary measures are considered to be resistant statistics?

A) the arithmetic mean and standard deviation

B) the interquartile range and range

C) the mode and variance

D) the median and interquartile range

Answer: D

14) According to the empirical rule, if the data form a “bell-shaped” normal distribution, ________ percent of the observations will be contained within 1 standard deviation around the arithmetic mean.

A) 68.26

B) 75.00

C) 88.89

D) 93.75

Answer: A

15) According to the Chebyshev rule, at least 93.75% of all observations in any data set are contained within a distance of how many standard deviations around the mean?

A) 1

B) 2

C) 3

D) 4

Answer: D

16) True or False: If the data set is approximately bell-shaped, the empirical rule will more accurately reflect the greater concentration of data close to the mean as compared to the Chebyshev rule.

Answer: TRUE

17) If two events are mutually exclusive, what is the probability that one or the other occurs?

A) 0

B) 0.50

C) 1.00

D) cannot be determined from the information given

18) If two equally likely events *A* and *B* are mutually exclusive and collectively exhaustive, what is the probability that event *A* occurs?

A) 0.

B) 0.50

C) 1.00

D) cannot be determined from the information given

Answer: B

19) If two equally likely events *A* and *B* are collectively exhaustive, what is the probability that event *A* occurs?

A) 0

B) 0.50

C) 1.00

D) cannot be determined from the information given

Answer: D

20) All the events in the sample space that are not part of the specified event are called

A) simple events.

B) joint events.

C) the sample space.

D) the complement of the event.

Answer: D

21) The employees of a company were surveyed on questions regarding their educational background (college degree or no college degree) and marital status (single or married). Of the 600 employees, 400 had college degrees, 100 were single, and 60 were single college graduates. The probability that an employee of the company does not have a college degree is ________.

A) 0.10

B) 0.33

C) 0.67

D) 0.75

Answer: B

22) The probability that house sales will increase in the next 6 months is estimated to be 0.25. The probability that the interest rates on housing loans will go up in the same period is estimated to be 0.74. The probability that house sales or interest rates will go up during the next 6 months is estimated to be 0.89. The probability that both house sales and interest rates will increase during the next 6 months is ________.

A) 0.10

B) 0.185

C) 0.705