THE NATURAL GAS CONSUMPTION CASE
Consider the situation in which a gas company wishes to predict weekly natural gas consumption
for its city. In the exercises of Chapter 13, we used the single predictor variable x, average hourly
temperature, to predict y
1. Pate's Pharmacy, Inc. operates a regional chain of 120 pharmacies. Each pharmacy's floor
plan includes a greeting card department which is relatively isolated. Sandra Royo, Marketing
Manager, feels that the level of lighting in the greeting card depart
Suppose that the random variable x has a uniform distribution with c = 2 and d = 8.
a.Write the formula for the probability curve of x, and write an interval that gives the
possible values of x.
b.Find P(3 x 5).
c.Find P(1.5 x 6.5).
d.Calculate the mean x
1. Suppose that the random variable x has an exponential distribution with = 2.
a. Write the formula for the exponential probability curve of x. What are the possible
values of x?
b. Find P(x 1).
c. Find P(.25 x 1).
d. Find P(x 2).
f. Calculate the mean,
1. Suppose that x has a binomial distribution with n = 200 and p = .4.
a. Show that the normal approximation to the binomial can appropriately be used to
calculate probabilities about x.
b. Make continuity corrections for each of the following, and then u
In the book Essentials of Marketing Research, William R. Dillon, Thomas J. Madden, and Neil
H. Firtle present the results of a concept study for a new wine cooler. Three hundred consumers
between 21 and 49 years old were randomly selected. After sampling
BUS 223 Exam 6 Chapters 13-14
1. A cost accountant is developing a regression model to predict the total cost of producing a
batch of printed circuit boards as a linear function of batch size (the number of boards produced
in one lot or batch), production
Counting Rules
Fundamental Counting Rule: for a sequence of 2
events in which the first can occur in m ways and the
second event can occur n ways, the events together
can occur a total of
ways.
Factorial Rule : n differenct items can be arranged in
order
33:AdditionRule
Whenrandomlyselectingonesubject,wheremeansthatAandBbothoccurinthesame
selection(trial).
Whentwoeventsaremutuallyexclusive,.
EX 1 Whatistheprobabilitythatthelastdigitofatelephonenumberis
a.
P(8or9).
b.
P(oddorlessthan4).
EX 2 Fromadeckof52c
Multiplication Rule
When randomly selecting more than one subject,
equals
alsoP(AB)
when A and B are independent or
withreplacement
when A and B are dependent.
withoutreplacement
ConditionalProbability
means:
P(B)givenAhappened.
EX1
In a group of 5 hair d
Addition Rule
AandB
A
B
NOtMutuallyExclusiveEvents
A
B
MutuallyExclusiveEvents
EX1
What is the probability that the last digit
of a telephone number is
a. P(8 or 9).
b. P(odd or less than 4).
EX2
From a deck of 52 cards, what is the
probability that the c
Rounding off probabilities: either give the exact fraction or
decimal or round results to three significant digits.
EX1
On an ACT test, a typical question has 5 possible
answers. If an examinee makes a random guess on
one such question, what is the probab