STA2023
Chapter 2
INSTRUCTIONS: Answer all questions. Shade the correct answer in your scantron for each of the questions on the quiz.
1. The first two classes of a frequency distribution are 0-19 and 20-39. What is the class width?
(a) 19 (b) 10 (c) 19.5 (d) 9.5 (e) 20
2. The first two classes of a frequency distribution are 0-19 and 20-39. What is the class mid-point for the second class?
(a) 20.5 (b) 19.5 (c) 14.5 (d) 29.5 (e) 39.5
3. What characteristic of a data set can be better understood by constructing a histogram?
(a) Shape (b) Variation (c) Center (d) Outliers (e) position
The test scores of 45 students are summarized in the frequency table below
Score
Students
20-29
5
30-39
10
40-49
15
50-59
10
60-69
5
4. What is the lower limit for the second class?
(a) 39.5 (b) 29.5 (c) 34.5 (d) 39 (e) 30
5. What is the class width in the frequency table above?
(a) 9 (b) 10 (c) 24.5 (d) 34.5 (e) 20
6. What is the class mid-point for the class 40 –49
(a) 34.5 b) 44.5 (c) 39.5 (d) 49.5 (e) 40
7. What are the upper limits for the last class?
(a) 60 (b) 69 (c) 59.5 (d) 69.5 (e) 64.5
8. What are the upper and lower boundaries for the third class?
(a) 39.5 – 49.5 (b) 40.5 – 49.5 (c) 40 – 49 (d) 34.5 – 44.5
9. What is the relative frequency corresponding to the frequency of 15 for the third class?
(a) 15% (b) 35% (c) 66.6% (d) 33.3% (e) 37.5%
10. What is the modal class?
(a) 20-29 (b) 30-39 (c) 40-49 (d) 50-59 (e) 60-69
11. What values are represented in the stemplot below?
stem
leaves
4
0
7
5
4
4
6
8
9
(a) 40, 47, 54, 59, 68, 60 (b) 41, 47, 54, 59, 68, 69
(c) 40, 47, 68, 61, 71, 76 (d) 40, 47, 54, 54, 68, 69
12. All of the following are characteristics of data EXCEPT:
(a) Center (b) Variation (c) Distribution (d) Position
13. Each of the following is a characteristic of a normal distribution EXCEPT:
(a) It is approximately symmetric
(b) It is approximately bell-shaped
(c) The number of data values preceding the maximum value is approximately the same as the number of values following the maximum value
(d) The frequencies start at zero, increases to a maximum and then decreases to zero
(e) The frequencies start low, then increase to one or two high frequencies, then decrease to a low frequency
14. A _________ is a graph consisting of bars of equal width drawn adjacent to each other. The horizontal scale represents classes of quantitative data values and the vertical scale represents frequencies. The heights of the bars correspond to the frequency values.
(a) Bar-Graph (b) Histogram (c) Frequency Polygon (d) Stemplot
15. True or False. When a die is rolled 600 times, each of the 6 possible outcomes occurs about 100 times as we normally expect, so the frequency distribution summarizing the results is an example of a normal distribution.
(a) True (b) False
16. Which graph is best for paired data consisting of the shoe size and heights of 30 randomly selected students?
(a) Histogram (b) dotplot (c) scatterplot (d) Pie Chart
17. Statistical graphs are used for each of the following EXCEPT
(a) To discover a trend or pattern over time
(b) To summarize a data set
(c) To facilitate computational procedures for solving probabilities
(d) To capture an audience attention
(e) To reinforce a critical point
18. True or false. In the construction of a frequency polygon, the class limits are used for the x axis.
(a) True (b) False
19. Data such as blood types (A, B, AB, O) can be organized by using a:
(a) Grouped frequency distribution (b) Stem and leaf plot
(c) Categorical frequency distribution (d) dotplot
20. True or False: If there are no data values for a particular class in a frequency distribution, that particular class can be eliminated.
(a) True (b) False
21. The first two classes of a frequency distribution are 0-9 and 10-19. What are the class boundaries for the second class?
(a) 9.5 & 10.5 (b) 9.5 & 19.5
(c) 10.5 & 19.5 (d) 10 & 19
22. What type of graph displays the data by using lines that connect points plotted for the frequencies at the midpoints of the classes?
(a) Histogram (b) Frequency Polygon (c) Cumulative frequency graph (d) Time series graph
23. What type of graph is used to visually represent the number of values that are below a certain upper class boundary?
(a) Histogram (b) Frequency Polygon (c) Cumulative frequency graph (d) Time series graph (e) Dot plot
24. All of the following are important characteristics of data EXCEPT
(a) Variation (b) Center (c) Distribution (d) Outliers (e) position
25. True or False. Quantitative variables can be summarized using frequency and relative frequency distributions.
(a) True (b) False
26. True or False. Stem and leaf displays contain more information than either a frequency distribution or histogram.
(a) True (b) False
27. What type of graph will best illustrate the changes in mean global temperatures from 1902 to 2015?
(a) Histogram (b) Bar graph (c) Time series graph (d) stem and leaf plot
Figure 1 below shows the emergency injuries suffered by 20,000 teenagers in the United States in 2014.
Figure 1
28. What is the most common injury?
(a) Fractures (b) Cuts and bruises (c) Other injury (d) Strains and sprains
29. Of the specific injuries shown, what is the least common injury?
(a) Strains & sprains (b) Cuts and bruises (c) Traumatic brain injury (d) Fractures
30. What is the percentage for cuts and bruises?
(a) 10% (b) 20% (c) 25% (d) 15% (e) 26%
31. What is the percentage for fractures?
(a) 25% (b) 20% (c) 15% (d) 26% (e) 24%
32. Approximately how many teenagers suffered traumatic brain injury in 2014?
(a) 1,800 (b) 2,000 (c) 200 (d) 180 (e) 2,400
Answer questions 33, 34, 35, and 36 on separate sheets of paper and turn in with your scantron.
33. The ages of the Vice Presidents of the United States at the time of their death are listed below. Construct a frequency distribution to summarize the data. Use 6 classes. List the relative and cumulative frequencies. List the class boundaries and class midpoints. Use Excel to construct a histogram to display the data.
90 83 80 73 70 51 68 79 70 71 72 74 67 54 81 66 62 63 68 57 66 96 78 55 60 66 57 71 60 85 76 98 77 88 78 81 64 66 77 70
34. Refer to the data set in question 33 above. Construct a stem and leaf plot to depict the ages of the vice-presidents at the time of their deaths.
35. Use EXCEL to construct a Pareto chart for the number of tons (in millions) of trash recycled per year by Americans based on an Environmental Protection Agency study.
Type
Amount
Paper
320
Iron/steel
282
Aluminum
268
Yard waste
242
Glass
196
Plastics
42
Source: USA TODAY
36. The table below shows the percentage of high school students who said they had used marijuana one or more times from 1991 to 2010. Construct a time-series chart to display the data.
Year
Percent of HS students using marijuana one or more times
1997
31
1998
32
1999
34
2000
35
2001
37
2002
41
2003
44
2004
48
2005
52
2006
50
2007
48
2008
47
2009
46
2010
45