Basic Probability and Statistics
HW3: sections 2.3 and 3.1
Section 2.3
Problem 18 (page 86) Math and Reading Achievement Scores
Construct a back-to-back stem and leaf plot with the data and compare the distributions.
Subject
Math
Math
Math
Math
Math
Math
Math
Math
Math
Math
Math
Math
Math
Math
Math
Math
Math
Math
Reading
Reading
Reading
Reading
Reading
Reading
Reading
Reading
Reading
Reading
Reading
Reading
Reading
Reading
Scores
52
63
55
68
66
57
59
76
69
59
74
73
62
59
72
61
55
73
65
71
61
77
76
70
69
77
76
70
78
80
66
66
1
Reading
Reading
Reading
Reading
76
67
61
77
Problem 21 (page 86) Meat Production
Meat production for veal and Lamb for the years 1960- 2000 is Shown here. (Data are in millions of
pounds.) Construct a compound time series graph for the data. What comparison can be made
regarding meat production?
Year
Veal
Lamb
1960
1109
769
1970
588
551
1980
400
318
1990
327
358
2000
225
234
Problem 24 (page 99) Recycled Trash
Construct a Pareto chart and a horizontal bar graph for the number of tons (in millions) of trash recycled
per year by Americans based on an Environmental Protection Agency study.
Type
Paper
Iron/steel
Aluminum
Yard waste
Glass
Plastics
Amount
320.0
292.0
276.0
242.4
196.0
41.6
Section 3.1
Problem 1 (page 118) Grade Point Average
The average undergraduate grade point average (GPA) for the 25 top-ranked medical schools is listed
below:
3.80
3.86
3.83
3.78
3.75
3.77
3.76
3.70
3.74
3.64
3.70
3.68
3.80
3.73
3.78
3.74
3.67
3.74
3.65
3.73
3.70
3.57
3.67
3.66
3.64
1. Find the (a) mean, (b) the median, (c) the mode, and (d) the midrange (without grouping)
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2. Find a, b, c, and d using a grouped frequency distribution with 5 classes.
Classes
Frequency (fm)
Midpoint (Xm)
fm * Xm
Total
Problem 20 (page 120) Commissions Earned
This frequency distribution represents the commission earned (in dollars) by 100 people employed at
several branches of a large chain store
Class Limits
Frequency (fm)
150-158
5
159-167
16
168-176
20
177-185
23
186-194
18
195-203
15
204-212
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Total
Find the (a) mean, (b) the median, and (c) the mode
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