Chapter 1: Overview and Descriptive Statistics
SOLUTION MANUAL
All Chapters Included
FOR
PROBABILITY AND STATISTICS
FOR
ENGINEERING AND THE SCIENCES
1
, Chapter 1: Overview and Descriptive Statistics
CHAPTER 1
Section 1.1
1.
a. Houston Chronicle, Des Moines Register, Chicago Tribune, Washington Post
b. Capital One, Campbell Soup, Merrill Lynch, Pulitzer
c. Bill Jasper, Kay Reinke, Helen Ford, David Menedez
d. 1.78, 2.44, 3.5, 3.04
2.
a. 29.1 yd., 28.3 yd., 24.7 yd., 31.0 yd.
b. 432, 196, 184, 321
c. 2.1, 4.0, 3.2, 6.3
d. 0.07 g, 1.58 g, 7.1 g, 27.2 g
3.
a. In a sample of 100 VCRs, what are the chances that more than 20 need
service while under warrantee? What are the chances than none need
service while still under warrantee?
b. What proportion of all VCRs of this brand and model will need service
within the warrantee period?
2
, Chapter 1: Overview and Descriptive Statistics
4.
a. Concrete: All living U.S. Citizens, all mutual funds marketed in the U.S.,
all books published in 1980.
Hypothetical: All grade point averages for University of California undergraduates
during the next academic year. Page lengths for all books published
during the next calendar year. Batting averages for all major league
players during the next baseball season.
b. Concrete: Probability: In a sample of 5 mutual funds, what is the chance
that all 5 have rates of return which exceeded 10% last year?
Statistics: If previous year rates-of-return for 5 mutual funds were 9.6, 14.5, 8.3,
9.9
and 10.2, can we conclude that the average rate for all funds was below 10%?
Conceptual: Probability: In a sample of 10 books to be published next year,
how likely is it that the average number of pages for the 10 is between
200 and 250?
Statistics: If the sample average number of pages for 10 books is 227,
can we be highly confident that the average for all books is between
200 and 245?
5.
a. No, the relevant conceptual population is all scores of all students who
participate in the SI in conjunction with this particular statistics course.
b. The advantage to randomly choosing students to participate in the two
groups is that we are more likely to get a sample representative of the
population at large. If it were left to students to choose, there may be a
division of abilities in the two groups which could unnecessarily affect the
outcome of the experiment.
c. If all students were put in the treatment group there would be no results
with which to compare the treatments.
6. One could take a simple random sample of students from all students in the
California State University system and ask each student in the sample to
report the distance form their hometown to campus. Alternatively, the sample
could be generated by taking a stratified random sample by taking a simple
random sample from each of the 23 campuses and again asking each student in
the sample to report the distance from their hometown to campus. Certain
problems might arise with self reporting of distances, such as recording error or
poor recall. This study is enumerative because there exists a finite,
identifiable population of objects from which to sample.
7. One could generate a simple random sample of all single family homes in the
city or a stratified random sample by taking a simple random sample from
each of the 10 district neighborhoods. From each of the homes in the sample
the necessary variables would be collected. This would be an enumerative
3
, Chapter 1: Overview and Descriptive Statistics
study because there exists a finite, identifiable population of objects from
which to sample.
4
SOLUTION MANUAL
All Chapters Included
FOR
PROBABILITY AND STATISTICS
FOR
ENGINEERING AND THE SCIENCES
1
, Chapter 1: Overview and Descriptive Statistics
CHAPTER 1
Section 1.1
1.
a. Houston Chronicle, Des Moines Register, Chicago Tribune, Washington Post
b. Capital One, Campbell Soup, Merrill Lynch, Pulitzer
c. Bill Jasper, Kay Reinke, Helen Ford, David Menedez
d. 1.78, 2.44, 3.5, 3.04
2.
a. 29.1 yd., 28.3 yd., 24.7 yd., 31.0 yd.
b. 432, 196, 184, 321
c. 2.1, 4.0, 3.2, 6.3
d. 0.07 g, 1.58 g, 7.1 g, 27.2 g
3.
a. In a sample of 100 VCRs, what are the chances that more than 20 need
service while under warrantee? What are the chances than none need
service while still under warrantee?
b. What proportion of all VCRs of this brand and model will need service
within the warrantee period?
2
, Chapter 1: Overview and Descriptive Statistics
4.
a. Concrete: All living U.S. Citizens, all mutual funds marketed in the U.S.,
all books published in 1980.
Hypothetical: All grade point averages for University of California undergraduates
during the next academic year. Page lengths for all books published
during the next calendar year. Batting averages for all major league
players during the next baseball season.
b. Concrete: Probability: In a sample of 5 mutual funds, what is the chance
that all 5 have rates of return which exceeded 10% last year?
Statistics: If previous year rates-of-return for 5 mutual funds were 9.6, 14.5, 8.3,
9.9
and 10.2, can we conclude that the average rate for all funds was below 10%?
Conceptual: Probability: In a sample of 10 books to be published next year,
how likely is it that the average number of pages for the 10 is between
200 and 250?
Statistics: If the sample average number of pages for 10 books is 227,
can we be highly confident that the average for all books is between
200 and 245?
5.
a. No, the relevant conceptual population is all scores of all students who
participate in the SI in conjunction with this particular statistics course.
b. The advantage to randomly choosing students to participate in the two
groups is that we are more likely to get a sample representative of the
population at large. If it were left to students to choose, there may be a
division of abilities in the two groups which could unnecessarily affect the
outcome of the experiment.
c. If all students were put in the treatment group there would be no results
with which to compare the treatments.
6. One could take a simple random sample of students from all students in the
California State University system and ask each student in the sample to
report the distance form their hometown to campus. Alternatively, the sample
could be generated by taking a stratified random sample by taking a simple
random sample from each of the 23 campuses and again asking each student in
the sample to report the distance from their hometown to campus. Certain
problems might arise with self reporting of distances, such as recording error or
poor recall. This study is enumerative because there exists a finite,
identifiable population of objects from which to sample.
7. One could generate a simple random sample of all single family homes in the
city or a stratified random sample by taking a simple random sample from
each of the 10 district neighborhoods. From each of the homes in the sample
the necessary variables would be collected. This would be an enumerative
3
, Chapter 1: Overview and Descriptive Statistics
study because there exists a finite, identifiable population of objects from
which to sample.
4
