PAM 2100
INSTRUCTOR: SALAM ABDUS
SAMPLE PRELIM QUESTIONS (PRELIM #1)
In total there will be 8 problems and 20 multiple choice questions. 8 problems
would be worth 60 points and the 20 multiple choice questions would be worth 40
points.
The problems will be similar to the problems which you have solved in problem
sets #1, #2 and #3. In what follows I have provided some sample questions for the
problems.
However, you should also review the problems in the problem sets
thoroughly.
I have also provided some samples for multiple choice questions.
However, the
practice problems that we have solved during the lectures are the best examples of the
multiple choice questions which will show up in the prelim, and you should review
them thoroughly.
In the prelim you will be provided with copies of table A. I will also give you the
equation for regression line. You can bring in
any
calculator.
Problem 1
a) Below is a stemplot of home runs hit by major league teams during a month.
What is the five
number summary of this data set?
2 1
3 5
4 0 3 9
5 1 2 3 4
6 4 8
7 5
Ans.
21
41.5
51.5
59
75
b) Consider a data set that includes every whole number from 1 to 51:
1, 2, 3, 4, 5, ….
. ,50, 51
What is the fivenumber summary of this data set?
Ans:
1
13
26
39
51
Problem 2
a) The median of x = 11 and the standard deviation of x = 7.
The variable x is linearly
transformed such that x
new
= 6x.
What is the median of x
new
?
What is the standard deviation of
x
new
?
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View Full DocumentRecall that multiplying each observation of a distribution by a positive number b multiplies
both measures of center (mean, median) and spread (IQR, s) by b.
The median of x
new
is (6)(11)= 66 and the standard deviation of x
new
is (6)(7)=42.
b) The mean of x = 10 and the standard deviation of x = 4.
The variable x is linearly transformed
such that x
new
= a + bx.
The mean of x
new
= 35 and standard deviation of x
new
= 12.
Suppose that
b
is a positive number. What does
a
equal?
What does
b
equal?
See answer to the problem no. 2 of problem set #2
Problem 3
Chocolate bars produced by a certain machine are labeled with 8.0 oz. The distribution of the
actual weights of these chocolate bars is normal with a mean of 8.1 oz. and a standard deviation
of 0.1 oz.
a) What proportion of chocolate bars weighs less than 8.0 oz? Round your value of z up to two
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 Spring '08
 ABDUS,S.
 Least Squares, Linear Regression, Regression Analysis, Standard Deviation, regression line

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