Stat 151.003 (Kozdron) Fall 2006
Solutions to Practice Problems for Midterm #2
1.
(a) An approximate 95% condence interval for the true daily parking revenues is
S
S
X z0.025 , X + z0.025
n
n
or
15
15
126 1.96 , 126 + 1.96
44
44
or
(121.6, 130.4).
(b) B
Stat 151.003 Fall 2006 (Kozdron)
Solutions to Assignment #3
1.
Review Exercise page 223 #10. Let J be the event that John will purchase a new car,
and let M be the event that Mary will purchase a new car. Then we know that P (J ) =
0.39, P (M ) = 0.73, an
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Stat 151.003 Fall 2006 (Kozdron)
Solutions to Assignment #5
Page 340 #10: We compute the sample mean for these 8 data points as
60 + 56 + 60 + 55 + 70 + 55 + 60 + 55
471
=
= 58.875.
8
8
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X=
2
S=
X2 (
n1
X )2
n
=
27911
7
4
Stat 151.003 Fall 2006 (Kozdron)
Solutions to Assignment #7
1. This is a very open-ended problem. A complete, reasonable solution contains the following
elements. Let 1 denote the true average age of married males, and let 2 denote the true age of
married
Stat 151.003 Fall 2006 (Kozdron)
Solutions to Assignment #6
1. Since there are less than 30 data points, and since the population standard deviation is unknown,
we will conduct a t-test. We calculate the sample mean X = 5.5 and the sample standard deviati
Statistics 151 Midterm #1 October 18, 2006
This exam has 4 problems and is worth 80 points.
Instructor: Michael Kozdron
You must answer all of the questions in the exam booklet provided.
You have 50 minutes to complete this exam. Please read all instructi
Stat 151.003 (Kozdron) Fall 2006
Practice Problems for Midterm #2
The following questions should constitute a portion of your review for Midterm #2. You are
responsible for all of the material covered in lecture and in the appropriate sections of the
text
Statistics 151 Midterm #2 November 15, 2006
This exam has 6 problems and is worth 50 points.
Instructor: Michael Kozdron
You must answer all of the questions in the exam booklet provided.
You have 50 minutes to complete this exam. Please read all instruct
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Stat 151.003 Fall 2006 (Kozdron)
Solutions to Assignment #4
Page 306 #16: If X denotes the life span of a portable radio, then X is normally distributed
with mean 3.1 years and standard deviation 0.9 years. That is, X is N (3.1, 0.92 ). If X denotes
the m