MAT 142 Summer Session 1
ANSWERS
Homework Day #9:
Name:______________________
I. Frequency Distributions
For problems 1 – 5 use the given frequency distribution.
Class
40 – 49
50 – 59
60 – 69
70 – 79
80 – 89
90 – 99
Frequency
6
5
2
7
8
3
1. What is the total number of observations?
2. What is the width of each class?
10
3. What is the midpoint of the third class?
4. What is the modal class(es)?
31
64.5
80 – 89
5. What would be the class limits of the next class IF an additional class were added to the frequency distribution?
100 – 109
For problems 6 – 8 use the following data which show the IQ scores of 50 GCC Freshmen.
80
89
92
95
97
100
102
106
81
89
93
95
98
100
103
108
87
90
94
97
99
100
103
108
88
91
94
97
100
100
103
108
89
92
94
97
100
101
104
109
6. Construct a frequency distribution with a first class of 78 – 86.
IQ
# of students
78 – 86
2
87 – 95
15
96 – 104
18
105 – 113
7
114 – 122
6
123 – 131
1
132 – 140
1
7. What is the width of each class? 9
8. What is the modal class(es) of your frequency distribution? 96 – 104
110
113
114
114
119
120
120
122
128
135
II. Statistical Graphs
9. A sample of 500 students who used the internet to book a spring break trip were asked which travel site they
used. The responses are summarized in the table below. Use this information to construct a circle graph illustrating
the percent of people who gave each response. Be sure to show your work just like I did in class.
Online Travel Site
Number of Bookings
Travelocity
175
Expedia
125
Orbitz
85
Other
115
The frequency distribution below indicates the heights of 45 GCC male students.
Height in inches
Number of GCC male students
64
2
65
6
66
7
67
9
68
10
69
6
70
3
71
0
72
2
10. Construct a Histogram
Height in inches
11. Construct a Frequency Polygon
Height in inches
12. Eighteen college students were asked how many college credits they had earned. The responses are organized
in the table below. Construct a stem-and-leaf display for this data.
10
42
33
15
53
45
Stem
1
2
3
4
5
6
24
60
48
Leaves
0
4
6
8
3
0
5
4
0
5
4
2
36
17
62
48
24
54
Note: 1 5
45
30
60
represents 15
7
3
2 5 8
0
13. Log on to the internet and navigate to http://www.mcwdn.org/Graphs/CirclePieQuiz.html
Take the online quiz and record your answers to the six (6) questions below.
1.
2.
3.
4.
5.
6.
Legend
Sleep and School
Meals and Homework
Sleep
8
School
14. Log on to the internet and complete the activity at
http://www.wisc-online.com/objects/index_tj.asp?objid=TMH1101
(click the next button at the bottom right of the page to progress through the activity)
Copy the result of YOUR stem and leaf plot that the activity asks you to do at the end of the exercise.
Stem
2
3
4
5
6
7
Note: 3 2
Leaves
8
2
1
0
0
0
4
3
1
1
8
6
5
2
2
6
9 9 9
3 4 5 7 7 8
3 8
represents 3.2