If the population from which we sample is highly skewed to the right or to the left, then
the population _________ might be a better measure of central tendency than the
population mean.
A. median
B. variance
C. mode
D. average
A random sample of size 1,000 is taken from a population where p = .20. Find P( > .
21).
A. .2148
B. .0239
C. .9761
D. .7852
During the past six months, 73.2 percent of US households purchased sugar. Assume
that these expenditures are approximately normally distributed with a mean of $8.22
and a standard deviation of $1.10. Find the probability that a household spent less than
$5.00 on sugar.
A. .9983
B. 0.000
C. 1.00
D. 0.0017
If the ________ limits are within the ________ limits, then it can be concluded that the
process is __________.
A. specification, natural, capable
B. natural, specification, stable
C. specification, natural, stable
D. natural, specification, capable
The number of items rejected daily by a manufacturer because of defects for the last 30
days are:
20, 21, 8, 17, 22, 19, 18, 19, 14, 17, 11, 6, 21, 25, 4, 19, 9, 12, 16, 16, 10, 28, 24, 6, 21,
20, 25, 5, 17, 8
Complete this frequency table for these data.
Transactional data are now used by businesses as part of
A. survey analysis.
B. big data.
C. descriptive statistics.
D. experimental studies.
The fill weight of a certain brand of adult cereal is normally distributed with a mean of
910 grams and a standard deviation of 5 grams. We calculated the value of z for a
specific box of this brand of cereal, and the z value was negative. This negative z value
indicates that
A. we made a mistake in our calculations, as z must always be a nonnegative number.
B. the fill weight exceeds 910 grams.
C. the fill weight is less than 910 grams.
D. the fill weight is equal to 910 grams.
E. the fill weight may be more or less than 910 grams depending on the value of the
standard deviation.
If = 16.1, = .03, and n = 6, calculate the natural tolerance limits.
A. [16.065, 16.135]
B. [16.088, 16.112]
C. [15.745, 16.455]
D. [16.055, 16.145]
According to a survey of adults, 64 percent have money in a bank savings account. If
we were to survey 50 randomly selected adults, find the mean number of adults who
would have bank savings accounts.
A. 12
B. 22
C. 32
D. 42
What is the probability that a king appears in drawing a single card from a deck of 52
cards?
A. 4/13
B. 1/13
C. 1/52
D. 1/12
E. 2/13
When making a decision in an environment of ________________, the likelihood of
each state of nature can be estimated.
A. certainty
B. uncertainty
C. risk
D. alternatives
The internal auditing staff of a local lawn-service company performs a sample audit
each quarter to estimate the proportion of accounts that are delinquent (more than 90
days overdue). For this quarter, the auditing staff randomly selected 400 customer
accounts and found that 80 of these accounts were delinquent. What is the 95 percent
confidence interval for the proportion of all delinquent customer accounts at this
company?
A. .1608 to .2392
B. .1992 to .2008
C. .1671 to .2329
D. .1485 to .2515
E. .1714 to .2286
The internal auditor for your company believes that 10 percent of your invoices contain
errors. To check this theory, 20 invoices are randomly selected, and 5 are found to have
errors. What is the probability that of the 20 invoices selected, 5 or more would contain
errors if the theory is valid?
A. .0433
B. .0319
C. .9567
D. .8660
As the margin of error decreases, the width of the confidence interval
_______________.
A. stays the same
B. decreases
C. increases
Math test anxiety can be found throughout the general population. A study of 116
seniors at a local high school was conducted. The following table was produced from
the data. Complete the missing parts.
How well the design of a product or service meets and exceeds the needs and
expectations of
the customer is called
A. process capability.
B. quality of conformance.
C. quality of performance.
D. quality of design.
E. process control.
The tolerance interval of 95.44 percent is ________ a 95.44 percent confidence interval.
A. the same width as
B. narrower than
C. wider than
Consider a normal population with a mean of 10 and a variance of 4. Find P(X > 18).
A. 1.00
B. 0.00
C. .9772
D. .0228
The expected _____________ of a decision maker is based upon his/her attitude toward
risk.
A. maximax
B. maximin
C. utility
D. risk theory
Alternatives 1 and 2 in the following payoff table represent the two possible
manufacturing strategies that the EKA manufacturing company can adopt. The level of
demand affects the success of both strategies. The states of nature (SI) represent the
levels of demand for the company products. S1, S2, and S3 characterize high, medium,
and low demand, with probabilities of .3, .6, and .1, respectively. The payoff values are
in thousands of dollars.
The management believes that weather conditions significantly affect the level of
demand. 48 monthly sales reports are randomly selected. These monthly sales reports
show 15 months with high demand, 28 months with medium demand, and 5 months
with low demand. 12 of the 15 months with high demand had favorable weather
conditions. 14 of the 28 months with medium demand had favorable weather
conditions. Only 1 of the 5 months with low demand had favorable weather conditions.
What is the probability that weather conditions are poor, given that the demand is high?
A. .2
B. .5
C. .8
D. .25
E. .75
__________ is a necessary component of a runs plot.
A. Observation over time
B. Qualitative variable
C. Random sampling of the data
D. Cross-sectional data
When the level of confidence and the sample size remain the same, a confidence
interval for a population mean μ will be ________________ when the sample standard
deviation s is small than when s is large.
A. wider
B. narrower
C. neither wider nor narrower (they will be the same)
Which percentile describes the third quartile, Q3?
A. 25th
B. 50th
C. 75th
D. 100th
The customer service manager for the XYZ Fastener Manufacturing Company
examined 60 invoices and found 9 that contained errors. Find a 98 percent confidence
interval for the proportion of invoices with errors.
A. [.147, .153]
B. [.080, .220]
C. [.043, .257]
D. [.112, .188]
In the one-way ANOVA, the treatment sum of squares equals
A. SSTO − SS(error) − SS(interaction).
B. SSTO − SS(factor 1) − SSE.
C. SSTO − SS(interaction) − SS(factor 1) − SS(factor 2).
D. SSTO − SS(factor 1) − SS(factor 2).
E. SSTO − SS(error).
Consider the following data on distances traveled by people to visit the local
amusement park and calculate the relative frequency for the distances over 24 miles.
A. .375
B. .150
C. .125
D. .025
E. .325
A machine is produced by a sequence of operations. Typically, one defective machine is
produced per 1000 parts. What is the probability of two nondefective machines being
produced?
A. 0.000999
B. 0.001
C. 0.002
D. 0.998
E. 0.500
Whenever the population has a normal distribution, the sampling distribution of is a
normal or near normal distribution
A. for only large sample sizes.
B. for only small sample sizes.
C. for any sample size.
D. for only samples of size 30 or more.
A ___________ index is a weighted aggregate price index that uses the base period
quantities as weights in all succeeding time periods.
A. Paasche
B. first-order autocorrelation
C. Laspeyres
D. cyclical (seasonal)
For a manufacturing process, = 10 inches, = .4 inches, and the subgroup sample size
is 6 units. Calculate the natural tolerance limits for this process.
A. [9.526, 10.474]
B. [9.510, 10.490]
C. [9.484, 10.516]
D. [9.807, 10.193]
E. [9.769, 10.231]
If you live in California, the decision to buy earthquake insurance is an important one.
A survey revealed that only 133 of 337 randomly selected residences in one California
county were protected by earthquake insurance. What is the p-value associated with the
test statistic calculated to test the claim that less than 40 percent of the county residents
are protected by earthquake insurance?
Consider the regression equation = 18.321 + 3.762(t) and the data below.
Compute the predicted value for sales for periods 6 and 7.
A manufacturer of an automobile part has a process that is designed to produce the part
with a target of 2.5 inches in length. In the past, the standard deviation of the length has
been 0.035 inches. In an effort to reduce the variation in the process, the manufacturer
has redesigned the process. A sample of 25 parts produced under the new process shows
a sample standard deviation of 0.025 inches. Calculate the test statistic for testing
whether the new process standard deviation has improved from the current process.
A baker must monitor the temperature at which cookies are baked. Too much variation
will cause inconsistency in the texture of the cookies. Past records show that the
variance of the temperatures has been 1.44 degrees. A random sample of 30 batches of
cookies is selected, and the sample variance of the temperature is 4.41 degrees. What is
the test statistic for testing the null hypothesis that the population variance has increased
above 1.44 degrees?
Employees of a local university have been classified according to gender and job type.
Are gender and type of job mutually exclusive?
A. Yes
B. No
In an opinion survey, a random sample of 1,000 adults from the United States and 1,000
adults from Germany were asked whether they supported the death penalty. 590
American adults and 560 German adults indicated that they supported the death penalty.
The researcher wants to know whether there is sufficient evidence to conclude that the
proportion of adults who support the death penalty is higher in the United States than in
Germany. What is the p-value for this test?
Using grouped data of 14 classes with a sample mean of 51 and a sample variance of
6.42, calculate the group sampled standard deviation.
When testing H0: μ1 − μ2 = 2, HA: μ1 − μ2 > 2, where = 522, = 516, σ12 = 28, σ22
= 24, n1 = 40, n2 = 30, at α = .01, what is the test statistic? (Assume unequal variances.)
Given the following data, compute the mean squared deviation (error).
A baker must monitor the temperature at which cookies are baked. Too much variation
will cause inconsistency in the texture of the cookies. Past records show that the
variance of the temperatures has been 1.44 degrees. A random sample of 30 batches of
cookies is selected, and the sample variance of the temperature is 4.41 degrees. Test the
hypothesis that the temperature variance has increased above 1.44 degrees at α = .05.
An experiment was performed on a certain metal to determine if the strength is a
function of heating time. The 95 percent confidence interval for the average strength of
a metal sheet when the average heating time is 4 minutes is from 4.325 to 5.675.
Therefore, we are confident at α = .05 that the average strength of this metal heated for
four minutes is between 4.325 and 5.675 pounds per square inch. Do you agree or
disagree with this statement?
A human resource manager is interested in whether absences occur during the week
with equal frequency. The manager took a random sample of 100 absences and created
the following table.
How many degrees of freedom are associated with the chi-square test? Use α = .05 and
determine the rejection point condition of the chi-square statistic.
Consider the following partial analysis of variance table from a randomized block
design with 6 blocks and 4 treatments.
Source Sum of Squares
Treatments 15.93
Blocks 42.09
Error 23.84
Total 81.86
What is the treatment mean square?
A U.S.-based company offers an online proficiency course in basic accounting.
Completing this online course satisfies the Fundamentals of Accounting course
requirement in many MBA programs. In the first semester, 315 students have enrolled
in the course. The marketing research manager divided the country into seven regions
of approximately equal population. The course enrollment values for each of the seven
regions are given below. The management wants to know if there is equal interest in the
course across all regions.
At a significance level of .01, test H0: the probabilities are equal for all seven regions.
To apply the p-value rule, determine the p-value for H0: p = .5; versus HA: p ≠.5, when
n = 225 and = .54.