This preview shows pages 1–3. Sign up to view the full content.
ECON 2843 – 010
Name
KEY
Exam 2
ID #
Fall 2006
Lab Instructor
Form B
Lab Meeting Time
Students must show all work on problems that involve calculation, even if the answer is multiple
choice.
Questions 1 – 3 refer to the following.
The dollar amounts for loans made to earthquake victims are normally distributed with a mean of
$6,000 and a standard deviation of $1,200.
1.
If we randomly sample nine of these loans, what is the probability that the sample mean
will be between $6,580 and $7,120?
(10 points)
a.
.0709
*
b.
.1394
c.
.6844
d.
.8606
e.
.9291
2.
If thirteen of these loans are randomly selected, what is the probability that the sample
variance will be more than 528,000?
(10 points)
.975
3.
Suppose that we randomly sample 64 of these loans. What is the probability at most 41
will have a dollar amount of $6,000 or more? (10 points)
.9878
1
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document4.
Circle true or false. As the sample size increases, the variance of the sample mean
becomes larger. (5 points)
True
False
5.
Circle true or false. The variance of the sample mean must always be larger than the
standard error of the sample mean.
(5 points)
This is the end of the preview. Sign up
to
access the rest of the document.
 Spring '08
 HUDGINS

Click to edit the document details