Download Name BUS271/PSY260 Exam 1 Questions 1 through 5 are multiple

Name ___________________________________________
BUS271/PSY260 Exam 1
1.
Questions 1 through 5 are multiple choice and are worth 1 point, each.
1.
Which of the following statements involve descriptive statistics (as opposed to inferential statistics)?
a. The Alcohol, Tobacco and Firearms Department reported that Houston had 1,791
registered gun dealers in 1997.
b. Based on a survey of 400 magazine readers, the magazine reports that 45% of its readers
prefer double column articles.
c. The FAA samples 500 traffic controllers in order to estimate the percent retiring due to job
stress related illness.
d. Based on a sample of 300 professional tennis players, a tennis magazine reported that 25%
of the parents of all professional tennis players did not play tennis.
2. The difference between the largest and smallest values in a data set is called the:
a.
b.
c.
d.
standard deviation.
variance.
range.
mean.
5.
3. The statistic that describes the midpoint of the data which has just as many values above it as below it
is known as the sample:
a.
b.
c.
d.
mean
median
mode
range
4. If an event of interest is labeled “A”, and the probability that A will occur is denoted P(A), then:
a.
b.
c.
d.
e.
the probability that A will not occur is [1 - P(A)].
the probability that A will not occur is the complement of A.
the probability is zero if event A is impossible.
the probability is one if event A is certain.
All of these are true.
5. A student is randomly selected from a class. If Event A = the student is a male and Event B = the
student is a female, then Events A and B are:
a.
b.
c.
d.
mutually exclusive.
intersecting.
dependent.
both A and B.
Name ___________________________________________
BUS271/PSY260 Exam 1
Questions 9 through 17 require a short answer. Some of the questions have multiple parts, but each
numbered question is worth a total of 3 points. Answer eight of these nine questions.
6. Find the range, median, and mode of the following data: 81, 97, 97, 58, 15, 94.
a. Range
82
b. Median
87.5
c. Mode
97
7. Calculate the variance and standard deviation for the following data: 8, 9, 8, 6, 4. Show your work.
8
9
8
6
4
7
7
7
7
7
1
2
1
-1
-3
Sum =
Variance =
Std. Dev =
1
4
1
1
9
16
16/4 = 4
2
Name ___________________________________________
BUS271/PSY260 Exam 1
8. Look at the table, below, on Project Management Software. If you were summarizing the software
prices, which of the measures of central tendency would you use to best represent the data? (Circle
one)
Mean and standard deviation, or
Median and the 5-number summary (minimum, Q1, median, Q2, maximum)
Briefly explain why you made your decision.
The price of the APECS software is an outlier that has a very large effect on the mean, but
almost no effect on the median.
9. Using this data set: 0, 0, 1, 1, 3, 3, 3, 5, 7, 7, 8, compute the values of Q1, Q2, Q3, and the
interquartile range.
Q1 = 1
Q2 = 3
Q3 = 7
IQR = 6
10. The table below indicates the number of students majoring in different subjects in a college of
business:
a. What is the probability that a randomly selected student in an accounting major?
11/85 = 0.1294
b. What is the probability that a randomly selected student is either a computer science or a
marketing major?
5/85 + 17/85 = 22/85 = 0.2588
a.
Name ___________________________________________
BUS271/PSY260 Exam 1
11. I have nine exams to grade, but only have time to grade four of them. Home many different
combinations of four exams can I grade? Order does not matter.
9 chose 4 = 126
12. The utility company in Opp found that 80% of its customers pay their monthly bill in full.
c. Suppose 2 customers are chosen at random from a list of all the customers. What is the
probability that both customers will pay their monthly bill in full?
.8 x .8 =.64
d. What is the probability that at least one will pay in full?
The easiest way to do this is to compute the probability that no one will pay in full:
.2 x .2 = .04
and subtract that value from 1. So, 1 - .04 = .96
13. The population distribution in the United States based on race, ethnicity and blood type as reported by
the American Red Cross is portrayed in this table.
Blood Type
Race/Ethnicity
O
A
B
AB
Total
White
360
322
88
32
802
Black
70
29
25
5
129
Asian
17
12
10
3
42
All others
15
8
3
1
27
Total
462
371
126
41
1000
a. A volunteer walks into a Red Cross office. What is the probability he will be white and
have blood type A?
P(White and A) = .322
b. What is the probability that an Asian donor will have blood type A or blood type B?
(12+10)/42 = .5238
OR
.012 + .10 = .022
c. What is the probability a volunteer will be black or have blood type AB?
P(Black or AB) = .129 + .041 - .005 = .165