This preview shows pages 1–4. Sign up to view the full content.
IOE 265 F2011
PRACTICE FINAL EXAM (2)Solutions
1 of 9
Part I. Multiple Choice (10 questions, 4 points each, 40 points total)
1. If
A
and
B
are disjoint or mutually exclusive events with
P
(
A
)
>
0 and
P
(
B
)
>
0, then
a.
P
=
P
(
A
)
+ P
(
B
)
b.
P
=
c.
P
=
P
(
A
)
+ P
(
B
)
d.
P
=
2.
If
are three independent random variables with variances of 2, 4, and 5, respectively,
then
is
a.
36
b.
12
c. 124
d.
140
3. How many combinations of size 2 can be constructed from the set (A, B, C, D, E, and
F)?
a.
60
b.
20
c. 15
d.
10
4. The cumulative distribution function
F
(
x
) of a discrete random variable
X
is given by
F
(0) = 0.30,
F
(1) =0 .70,
F
(2) = 0.90, and
F
(3) = 1.0, then the value of the probability
mass function
p
(
x
) at
x
= 1 is
a.
0.30
b. 0.40
c.
0.20
d.
0.80
5. Let
X
be a discrete random variable with
E
(
X
) = 8.6.
Then
E
(3
X
+ 5.6) is
a. 31.4
b.
14.2
c.
25.8
d.
77.4
6. Which of the following is not a condition of a binomial experiment?
a.
There is a sequence of
n
identical trials.
b. Each trial results in at least two outcomes.
c.
The trials are independent of each other.
d.
The probability of success
p
is constant from one trial to another.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document IOE 265 F2011
PRACTICE FINAL EXAM (2)Solutions
2 of 9
7. If
X
is a normally distributed random variable with a mean of 25 and a standard
deviation of 8, then the probability that
X
exceeds 20 is approximately
a.
0.27
b.
0.37
c.
0.62
d. 0.73
8. Which of the following statements are true if
is a random sample from a distribution
with mean ?
a.
b.
c.
d.
9. If
X
is a nonnegative random variable and the random variable
Y
= LN(
X
)
is normally
distributed with parameters, then which of the following statements are not true?
a.
X
is a lognormal random variable.
b. The parameters
are the mean and standard deviation of
X
.
c.
The parameters
are the mean and standard deviation of
Y.
d.
Y
has a symmetric distribution.
10. If
P
(AB)
= P
(A), and
P
(BA)
= P
(B)
,
then events
A
and
B
are said to be:
a. independent
b.
mutually exclusive
c.
dependent
d.
complementary
IOE 265 F2011
PRACTICE FINAL EXAM (2)Solutions
3 of 9
Part II.
Briefly
answer the following questions (10 points each, 20 points total) – Do not
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview. Sign up
to
access the rest of the document.
This note was uploaded on 01/05/2012 for the course IOE 265 taught by Professor Jin during the Fall '07 term at University of Michigan.
 Fall '07
 Jin

Click to edit the document details