The national sales manager for “I colored this” (ICT) T-shirts provides all salespersons
with the payoff table shown next, giving the estimated profit when a retailer purchases
from one to four dozen T-shirts. The probability of demand for each state of nature is
also shown.
What is the expected payoff for purchasing two dozen T-shirts?
A. 72
B. 120
C. 168
D. 192
A company is studying the number of monthly absences among its 125 employees. The
following probability distribution shows the likelihood that people were absent 0, 1, 2,
3, 4, or 5 days last month.
Given the probability distribution, which of the following predictions is correct?
A. 60% of the employees will have more than one day absent per month.
B. There is a 0.04 probability that an employee will be absent one day per month.
C. There is a 0.12 probability that an employee will be absent two days per month.
D. There is a 0.50 probability that an employee will be absent 0.72 days per month.
A university wishes to conduct a student survey. In one of the questions students are
asked to mark their gender as either male or female. Gender is an example of the:
A. Ordinal scale
B. Nominal scale
C. Ratio scale
D. Interval scale
If the coefficient of multiple determination is 0.81, what percent of variation is not
explained?
A. 19%
B. 90%
C. 66%
D. 81%
A survey of households in a small town showed that in 500 of 1,200 sampled
households, at least one member attended a town meeting during the year. Using the
95% level of confidence, what is the confidence interval for the proportion of
households represented at a town meeting?
A. [0.417, 0.427]
B. [0.389, 0.445]
C. [0.400, 0.417]
D. [0.417, 0.445]
A nonparametric test:
A. assumes that the populations are normally distributed.
B. assumes that the populations have equal standard deviations.
C. makes no assumptions about the population distributions.
D. assumes that the populations follow a standard normal distribution.
The following are the ratings (0 to 4) given by 12 individuals for two possible new
flavors of soft drinks.
Wilcoxon rank-sum is to be used.
What is the sum of the ranks for flavor #1?
A. 144
B. 139
C. 156
D. 153
For a standard normal distribution, what is the probability that z is greater than 1.75?
A. 0.0401
B. 0.0459
C. 0.4599
D. 0.9599
If there are four independent variables in a multiple regression equation, there are also
four ______.
A. Y-intercepts
B. Regression coefficients
C. Dependent variables
D. Constant terms
The probability of an event that is affected by two or more different events is called a(n)
___________.
A. Conditional probability
B. Empirical probability
C. Joint probability
D. Tree diagram
The coefficient of determination measures the proportion of ____________.
A. Explained variation relative to total variation
B. Variation due to the relationship among variables
C. Error variation relative to total variation
D. Variation due to regression
During the past six months, a purchasing agent placed the following three orders for
coal:
What is the weighted arithmetic mean price per ton?
A. $87.25
B. $72.33
C. $68.47
D. $89.18
Random samples of four items are selected from a manufacturing process at regular
intervals and a certain quality characteristic is measured. After 25 samples, ΣX =
15,350 and ΣR = 411.4. What is the sample size?
A. 4
B. 25
C. 100
D. 20
The Consumer Price Index in June 2006 was 159.3 (1982-84 = 100). What does this
indicate about prices from 1982-84 to June 2006?
A. Rose 59.3%
B. Rose 100.0%
C. Rose 159.3%
D. Declined 159.3%
Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches
41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that
they watch the late evening news on this local CBS station. What is the alternate
hypothesis?
A. H1: π = 0.36
B. H1: π = 0.41
C. H1: π ≠0.41
D. H1: ≠0.41
If an average of 60 customers are served per hour, then one customer arrives every
________.
A. 1 minute
B. 60 minutes
C. 12 minutes
D. 10 minutes
Two accounting professors decided to compare the variance of their grading procedures.
To accomplish this, they each graded the same 10 exams, with the following results:
At the 1% level of significance, what is the decision?
A. Reject the null hypothesis and conclude the variances are different.
B. Fail to reject the null hypothesis and conclude the variances are different.
C. Reject the null hypothesis and conclude the variances are the same.
D. Fail to reject the null hypothesis and conclude the variances are the same.
Using the following data, the Wilcoxon signed-rank hypothesis test is used to test the
hypothesis that the test results of a treatment after training are greater than the test
results before the treatment. The Wilcoxon critical value is 3 for n = 7 with a 0.05
significance level. What decision should be made regarding the null hypothesis?
A. Reject the null hypothesis and conclude that the “after” is greater than “before.”
B. Reject the null hypothesis and conclude that the “before” is greater than “after.”
C. Fail to reject the null hypothesis.
D. Reject the null hypothesis and conclude that there is no difference between the
“before.” and “after.”
For a distribution of sample means constructed by sampling 5 items from a population
of 15, ___________.
A. the sample size is 15
B. there will be 3,003 possible sample means
C. the mean of the sample means will be 3
D. the standard error will be 1
When all the items in a population have an equal chance of being selected for a sample,
the process is called _________________.
A. simple random sampling
B. z-score
C. sampling error
D. nonprobability sampling
In a Kruskal-Wallis test, the null hypothesis states equality among five different
populations. The sample size for each population exceeds five. What is the critical value
for the test using a 0.05 significance level?
A. 1.960
B. 5.05
C. 9.488
D. 2.776
The Consumer Price Index is ______________.
A. an annual price index published by the Bureau of Labor Statistics to measure the
percent change in stock market indexes such as the DJIA
B. a Laspeyres index that allows consumers to determine the degree to which their
purchasing power is being eroded by price increases
C. a monthly price index that measures the change in price of a fixed market basket of
goods and services from one period to another
D. both a Laspeyres index that allows consumers to determine the degree to which their
purchasing power is being eroded by price increases and a monthly price index that
measures the change in price of a fixed market basket of goods and services from one
period to another
In a uniform distribution, with a minimum, a, and maximum, b, the probability that the
random variable, x, is between a and (b – a)/2 is ___________.
After arriving at the university student medical clinic, the waiting times to receive
service after checking-in follow an exponential distribution with a mean of 10 minutes.
Calculate the probability a student waits more than 12 minutes.
A collection of one or more possible outcomes of an experiment is called a(n)
___________.
LongLast Inc. produces car batteries. The mean life of these batteries is 60 months. The
distribution of the battery life closely follows the normal probability distribution with a
standard deviation of eight months. As a part of its testing program, LongLast tests a
sample of 25 batteries. What proportion of the samples will have a mean useful life of
more than 56 months?
A student is planning a trip home for the holidays and has three options: car, train, or
jet. The decision depends on if the weather is good or bad. In addition, the student
estimated the costs for each option. The payoff table follows.
What is the expected value of taking the train?
The proportion of the area under a normal curve that is to the left of z = 1.40 is
_______.