Data show that the weight of an offensive linesman may be any weight between 200
and 350 pounds. The distribution of weight is based on a ______________.
A. continuous random variable
B. discrete random variable
C. qualitative variable
D. All apply.
The following is Jim Walker’s income for 1995 and 2007.
What was Jim’s real income for 2007?
A. $37,000
B. $67,000
C. $34,387
D. $38,908
A survey of top executives revealed that 35% of them regularly read Time magazine,
20% read Newsweek, and 40% read U.S. News & World Report. A total of 10% read
both Time and U.S. News & World Report. What is the probability that a particular top
executive reads either Time or U.S. News & World Report regularly?
A. 0.85
B. 0.06
C. 1.00
D. 0.65
Shoe style is an example of what level of measurement?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
A new machine that fills tubes of toothpaste will be monitored using statistical process
control. The following data were collected while the machine was closely monitored
and under control. Each day a random sample of six tubes are weighed. Based on the
data, the process mean is 6.752.
What is the lower control limit for the x-bar chart rounded to three decimal places?
A. 6.816
B. 6.676
C. 6.688
D. 6.828
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.
At the 0.05 level of significance, what is the decision?
A. Fail to reject null hypothesis; critical value is 1.65.
B. Fail to reject null hypothesis; critical value is 1.96.
C. Reject null hypothesis; critical value is 0.1732.
D. Reject null hypothesis; critical value is 0.3464.
Which of the following values of Spearman’s (rho) indicates the strongest relationship
between two variables?
A. -0.91
B. -0.05
C. +0.64
D. +0.89
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 null hypothesis?
A. H0: π = 0.36
B. H0: π = 0.41
C. H0: π ≠0.36
D. H0: = 0.41
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 assumed equal. What is the critical t value at the 1% level of significance?
A. +2.797
B. -2.492
C. 1.711
D. 2.797
In the Kruskal-Wallis test, the degrees of freedom are:
A. the total number of observations less one.
B. the total number of observations.
C. the number of populations less one.
D. each sample size less one.
The Durbin-Watson statistic is based on the:
A. differences between successive residuals in a time series.
B. differences between successive sales in a time series.
C. differences between typical sales indexes.
D. differences in time periods.
Data for fuel oil and gasoline purchased at wholesale prices for 2006 and 2010 are
shown next.
What is the unweighted aggregate price index?
A. 116.45
B. 116.71
C. 116.67
D. 131.56
Of the following characteristics, the t distribution and z distribution are the same in all
BUT one. Which one is it?
A. Continuous
B. Symmetrical
C. Bell-shaped
D. Mean = 0, and standard deviation = 1
What is the lowest level of measurement to which a median can be computed?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
When using Student’s t to compute an interval estimate, ___________.
A. we assume that the samples are collected from populations that are uniformly
distributed
B. we estimate the population mean based on the sample mean
C. we use the z distribution
D. we assume that the samples are collected from normally distributed populations
The distribution of a sample of the outside diameters of PVC pipes approximates a
symmetrical, bell-shaped distribution. The arithmetic mean is 14.0 inches, and the
standard deviation is 0.1 inches. About 68% of the outside diameters lie between what
two amounts?
A. 13.5 and 14.5 inches
B. 13.0 and 15.0 inches
C. 13.9 and 14.1 inches
D. 13.8 and 14.2 inches
The distribution of Student’s t has _________.
A. a mean of zero and a standard deviation of one
B. a mean of one and a standard deviation of one
C. a mean of zero and a standard deviation that depends on the sample size
D. a mean that depends on the sample size and a standard deviation of one
The time to fly between New York City and Chicago is uniformly distributed with a
minimum of 120 minutes and a maximum of 150 minutes. What is the probability that a
flight is between 125 and 140 minutes?
A. 1.00
B. 0.50
C. 0.33
D. 10.00
How can indexes be classified?
A. Price
B. Quantity
C. Value
D. Weighted or unweighted
Of the three components in any decision-making situation, which of the following
cannot be controlled?
A. Alternatives
B. Payoff
C. States of nature
D. Seasonal indexes
Which one of the following is not a component of a time series?
A. Secular trend
B. Moving average
C. Seasonal variation
D. Irregular variation
For a hypothesis comparing two population means, H0: μ1≤ μ2, what is the
critical value for a one-tailed hypothesis test, using a 5% significance level, with both
sample sizes equal to 13? Assume the population standard deviations are equal.
A. 1.711
B. +1.711
C. +2.060
D. +2.064
The joint probability of two events, A and B, that are not independent is computed as
P(A and B) = P(A) P(B|A).
Data for selected vegetables purchased at wholesale prices for 1995 and 2007 are
shown next.
What is the unweighted aggregate price index?
A. 98.4
B. 107.0
C. 117.5
D. 128.8
Which chi-square distribution would be closest to a normal distribution?
A. The distribution with 3 degrees of freedom.
B. The distribution with 12 degrees of freedom.
C. The distribution with 15 degrees of freedom.
D. The distribution with 9 degrees of freedom.
A sample of five full-service gasoline stations, each carrying three grades of gasoline,
was taken, and the price per liter (to the nearest cent) was recorded for each grade of
gasoline, as shown in the following table.
What is the median price of unleaded plus gas?
For the standard normal distribution, the z-score that corresponds with the first quartile
is ________.
A machine cuts steel to length for nails. The mean length of a nail is 43 millimeters.
There is concern that the settings of the machine producing the nails have changed. To
test the claim, 12 nails (n = 12) were sampled. The mean of the sample is 41.5 and the
standard deviation is 1.784. To test the claim at the 0.02 significance level, what is the
critical value?
Five students were given a page of problems with instructions to solve as many as they
could in one hour. The five students solved the following number of problems: 12, 10,
8, 6, and 4. What is the arithmetic mean number of minutes required per problem?
In a fishbone diagram, “dissatisfied customers” would be an _________ and ‘slow
service” would be a _________.
The Wilcoxon signed-rank test requires the populations to be _____________.
Pearson’s coefficient of skewness (Sk) ranges from -3.0 to +3.0. It is computed by
subtracting the median from the mean, multiplying the result by 3, and dividing by the
_______________.
To apply the special rule of addition, the events must be _________.
A sample of five full-service gasoline stations, each carrying three grades of gasoline,
was taken, and the price per liter (to the nearest cent) was recorded for each grade of
gasoline, as shown in the following table.
What is the median price of unleaded gas?