Ian Harbus
01/12/17
Chapter 12, Correlation and Regression
Problem Set 9
Problem 1:
a. The independent variable would be the age, and the dependent variable would be the
fatalities.
b. The independent variable would be the number of family members, the de
Ian Harbus
01/09/17
Problem Set #6
Problem 1
a) X ~ N(100, 15)
b)
The z-score: z = (120 100)/15 = 1.333 using the table to find that P(0 < z < 1.33) =
0.408; which equals P(X > 120) = P(Z > 1.33) = 0.5 0.408 = 0.092
c)
Using the table, z-score of z = 2.06
Math 161B
Quiz 3
Solution
12 February 2014
8
6
4
The MushiMints that weighed 1.40 grams or
more are the ones in highest two classes. There
are 9 + 6 = 14 such candies, and 14 is 35% of
Weight (grams)
40.
Thus, 35% of the candies in the sample had weights
Math 161B
Quiz 7
Solution
2 April 2014
1. Find the z -score that separates the highest 27% of the values of a standard normal
random variable from the rest.
to be (100 27)% = 73%, or 0.7300.
Solution: We want the area to the left of z =
Area = 0.7300
0
z
Math 161B
Quiz 6
Solution
26 March 2014
1. To play the Five-Ten Lottery, you pay an entry fee of $1 and select ve numbers from
the set cfw_1, 2, 3, . . . , 10. The Lottery Commission then selects ve winning numbers
from the same set. If the winning number
Math 161B
Quiz 5
Solution
26 February 2014
1. There are 174 seniors enrolled at the Fiction County Preparatory School. According
to the FCPS registrar, 38 of the seniors are taking Advanced Biology and 31 of the
seniors are taking Advanced Chemistry. Ther
Math 161B
Quiz 4
Solution
19 February 2014
1. The stem-and-leaf diagram at right gives the weights
(in pounds) of the members of the long-jump squad
at the Khalada Day School.
18
17
16
15
14
5
2
0
0
4
5
1
0
7
667
4779
2358
8
(a) Find the rst quartile for
Math 161E
Hour Exam I Solutions
5 March 2014
1. Carefully describe the statistic and the parameter in the following situation.
A researcher randomly selects fty single-family homes in the Chicago
metropolitan area, looks up the assessed value of each home
Math 161 B and E
Solutions
Exam I Practice Problems
26 February 2014
1. (a) Carefully describe the sample and the population in the following situation.
A buyer for a clothing distributor, upon receiving a large shipment of
shirts from the factory, random
Math 161B
Quiz 1
Solution
31 January 2014
1. Carefully describe the population and the parameter in the following situation:
The circulation sta at Acquisitor Magazine sends a questionnaire to every
one of the magazines 52,000 subscribers. Only 852 subscr
Math 161B
Hour Exam I Solutions
5 March 2014
1. Carefully describe the statistic and the parameter in the following situation.
A researcher randomly selects fty single-family homes in the Chicago
metropolitan area, looks up the assessed value of each home
Math 161 B and E
Exam I Practice Problems
26 February 2014
1. (a) Carefully describe the sample and the population in the following situation.
A buyer for a clothing distributor, upon receiving a large shipment of
shirts from the factory, randomly selecte
Math 161B
Quiz 2
Solution
5 February 2014
1. The stem-and-leaf diagram at right shows the grade
point averages (GPAs) of the members of the Junior
Honors Club at Eastern Elite University.
What are the fth-highest and fth-lowest GPAs in
the club?
Solution:
Math 484
Problem Set #7 Solution
28 March 2014
1. A cube has twelve edges. The symmetry group of the cube has
24 elements. One element is the identity, and there are four other
types of elements (technically, these are four conjugacy classes).
(a) For eac
Math 484
Problem Set #4 Solution
28 February 2014
1. (B&W Exercise 1.4.8) For each n > 0, let Bn denote the total number of partitions of
n. That is,
cfw_ cfw_
cfw_
n
n
n
Bn =
+
+ +
.
1
2
n
For convenience, we dene B0 = 1. There is one partition of cfw_,
Math 484
Problem Set #2 Solution
12 February 2014
1. Consider an ordinary deck of 52 playing cards supplemented by two wild cards, W1 and
W2. In a poker hand, a wild card can be used as any card (including those in a fth
suit), but it must always be used
Math 484
Problem Set #6 Solution
14 March 2014
1. We decorate the vertices of a regular pentagon using one white bead, two black beads,
(
)
5
and two red beads. If the pentagon is xed, then there are
= 30 ways to do
221
this.
Let S denote the set of these
Math 484
Problem Set #3 Solution
24 February 2014
1. (a) Use a spreadsheet program to construct a table of the Stirling numbers of the
cfw_
n
second kind,
, for 1 n 10, and 1 k 10.
k
(This was the last exercise on our computer lab worksheet.)
Solution: He
Math 484
Problem Set #1 Solution
5 February 2014
1. Use the Rule of Product (Theorem 1.2) to count the number of even four-digit positive
integers. Explain how the even four-digit positive integers correspond to a particular
Cartesian product.
Solution: W
Math 484
Problem Set #5 Solution
7 March 2014
1. Let S10 denote the set of permutations of 10.
(a) How many 5-cycles are there in S10 ?
Solution: Here is a solution in the spirit of Bender & Williamson. Let N be
the number of 5-cycles. We count the number