A population consists of all the weights of all defensive tackles on a university’s
football team. They are Johnson, 204 pounds; Patrick, 215 pounds; Junior, 207 pounds;
Kendron, 212 pounds; Nicko, 214 pounds; and Cochran, 208 pounds. What is the
population standard deviation (in pounds)?
A. About 4
B. About 16
C. About 100
D. About 40
An index of clothing prices for 2006 based on 1985 is to be constructed. The prices for
1985 and 2006 and the quantity consumed in 1985 are shown next.
Assuming that the number sold remained constant (i.e., the same number were sold in
2006 as in 1985), what is the weighted index of price for 2006 using 1985 as the base?
A. 206.7
B. 214.5
C. 48.4
D. 46.6
Refer to the following distribution of ages:
What is the class interval?
A. 9
B. 10
C. 10.5
D. 11
The manager of Paul’s fruit and vegetable store is considering the purchase of a new
seedless watermelon from a wholesale distributor. Since this seedless watermelon costs
$4, will sell for $7, and is highly perishable, he only expects to sell between six and
nine of them. What is the opportunity loss for purchasing six watermelons when the
demand is for eight watermelons?
A. 0
B. 3
C. 4
D. 6
Data for fuel oil and gasoline purchased at wholesale prices for 2006 and 2010 are
shown next.
What is the interpretation of the value index?
A. Value rose 16.67%.
B. Value rose 31.56%.
C. Value rose 16.71%.
D. Value rose 16.45%.
A person is trying to decide if they should buy a lottery ticket. The ticket costs $2.00. If
the ticket is a winner, the prize would be $1,000. Knowing that winning $1,000 is not a
certain outcome (state of nature), the person finds that the probability of winning is
0.001. Based on this information, the following payoff table can be constructed:
What is the decision using a maximax or optimistic approach?
A. Buy
B. Don’t buy
C. Lose
D. Win
A national manufacturer of ball bearings is experimenting with two different processes
for producing precision ball bearings. It is important that the diameters be as close as
possible to an industry standard. The output from each process is sampled and the
average error from the industry standard is measured in millimeters. The results are
presented next.
The researcher is interested in determining whether there is evidence that the two
processes yield different average errors. The population standard deviations are
unknown but are assumed equal. This example is what type of test?
A. A one-sample test of means
B. A two-sample test of means
C. A paired t-test
D. A test of proportions
If Gallup, Harris, and other pollsters asked people to indicate their political party
affiliation as Democrat, Republican, or Independent, the data gathered would be an
example of which scale of measurement?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
In constructing a frequency distribution, the approximate class width is computed as
A. (maximum value – minimum value)/(number of classes)
B. (maximum value – minimum value)/(sample size)
C. (minimum value – maximum value)/(sample size)
D. (maximum value)/(number of classes – sample size)
A manufacturer of automobile transmissions uses three different processes.
Management ordered a study of the production costs to see if there is a difference
among the three processes. A summary of the findings is shown next.
In an ANOVA table, what are the degrees of freedom for the treatment source of
variation?
A. 2
B. 3
C. 10
D. 27
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 5% level of significance, what is the decision regarding the null hypothesis?
A. Reject the null hypothesis and conclude the variances are different.
B. Fail to reject the null hypothesis and conclude no significant difference in the
variances.
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.
A sales manager for an advertising agency believes there is a relationship between the
number of contacts that a salesperson makes and the amount of sales dollars earned.
A regression analysis shows the following results:
= 33.4. = 2814.4.
The 95% prediction interval for a particular person making 30 calls is _______.
A. 55.8, 51.5
B. 51.4, 55.9
C. 46.7, 60.6
D. 31.1, 76.2
Why are long-range predictions considered essential to managing a firm?
A. To develop plans for possible new plants
B. To have raw materials available for future demand
C. To develop plans for future financing
D. All of these
A company’s headquarters is located in downtown Chicago. If they require their
employees to start working at 6:00 a.m., the company is interested to know the mean
driving time of its employees. Fifty employees are randomly sampled over four weeks
and asked to record their driving times. The mean driving time is 35 minutes, with a
standard deviation of 10 minutes. What is the 98% confidence interval for the
population mean?
For the most recent seven years, the U.S. Department of Education reported the
following number of bachelor’s degrees awarded in computer science: 4,033; 5,652;
6,407; 7,201; 8,719; 11,154; 15,121. What is the annual arithmetic mean number of
degrees awarded?
A. About 12,240
B. About 8,327
C. About 6,217
D. About 15,962
A Pareto chart is useful because it is based on the theory that 80% of the observations
are accounted for by 20% of the ________.
When planning an experiment, how is a significance level related to sample size?
In the _______________________ distribution, the probability of a success is not the
same on each trail.
The branch of statistics that does not involve generalizations is called ______________.
What are the similarities and differences between the mean, the median, and the mode?
A resort hotel performed a quarterly time series analysis for demands over the last five
years (periods 1 through 20). The analysis resulted in the following trend equation and
seasonal indexes:
Ŷ = 1000 + 150t
Based on the seasonal indexes, which quarter is expected to have 20% less demand than
predicted by the trend line?
In a bar chart, why are there spaces between the bars on the horizontal axis?
The following frequency distribution shows the distribution of delivery times (in days)
for swimstuff.com customer orders during the last month.
How many orders were delivered in three days or more?