Exhibit 18-6
It is believed that the median yearly income in a suburb of Atlanta is $70,000. A sample
of 67 residents was taken. Thirty-eight had yearly incomes above $70,000, 26 had
yearly incomes below $70,000, and 3 had yearly incomes equal to $70,000. The null
hypothesis to be tested is H0: median = $70,000.
Refer to Exhibit 18-6. The p-value for this test is
a. 0.4332
b. 0.8664
c. 0.0668
d. 0.1336
Of five letters (A, B, C, D, and E), two letters are to be selected at random. How many
possible selections are there?
a. 20
b. 7
c. 5!
d. 10
Exhibit 10-9
Two major automobile manufacturers have produced compact cars with the same size
engines. We are interested in determining whether or not there is a significant difference
in the MPG (miles per gallon) of the two brands of automobiles. A random sample of
eight cars from each manufacturer is selected, and eight drivers are selected to drive
each automobile for a specified distance. The following data show the results of the test.
Refer to Exhibit 10-9. The mean for the differences is
a. 0.50
b. 1.5
c. 2.0
d. 2.5
From a population that is not normally distributed and whose standard deviation is not
known, a sample of 50 items is selected to develop an interval estimate for
. Which of
the following statements is true?
a. The standard normal distribution can be used.
b. The t distribution with 50 degrees of freedom must be used.
c. The t distribution with 49 degrees of freedom must be used.
d. The sample size must be increased in order to develop an interval estimate.
The Malcolm Baldrige National Quality Award was established in
a. 1954
b. 1971
c. 1987
d. 1993
In acceptance sampling, the risk of rejecting a good quality lot is known as
a. consumer’s risk
b. producer’s risk
c. a Type II error
d. None of the other answers is correct
A graphical device for depicting categorical data that have been summarized in a
frequency distribution, relative frequency distribution, or percent frequency distribution
is a(n)
a. histogram
b. stem-and-leaf display
c. ogive
d. bar chart
It is impossible to construct a frame for a
a. finite population
b. infinite population
c. target population
d. sampled population
A student believes that no more than 20% (i.e., 20%) of the students who finish a
statistics course get an A. A random sample of 100 students was taken. Twenty-four
percent of the students in the sample received A’s.
a. State the null and alternative hypotheses.
b. Using a critical value, test the hypothesis at the 1% level of significance.
c. Using a p-value, test the hypothesis at the 1% level of significance.
The weights of the contents of cans of tomato paste produced by a company are
normally distributed with a mean of 6 ounces and a standard deviation of 0.3 ounces.
a. What percentage of all cans produced contains more than 6.51 ounces of tomato
paste?
b. What percentage of all cans produced contains less than 5.415 ounces?
c. What percentage of cans contains between 5.46 and 6.495 ounces?
d. Ninety-five percent of cans will contain at least how many ounces?
e. What percentage of cans contains between 6.3 and 6.6 ounces?
The variable of interest in an ANOVA procedure is called
a. a partition
b. a treatment
c. either a partition or a treatment
d. a factor
A lottery is conducted using three urns. Each urn contains chips numbered from 0 to 9.
One chip is selected at random from each urn. The total number of sample points in the
sample space is
a. 30
b. 100
c. 729
d. 1,000
In order not to violate the requirements necessary to use the chi-square distribution,
each expected frequency in a goodness of fit test must be
a. at least 5
b. at least 10
c. no more than 5
d. less than 2
In point estimation, data from the
a. population is used to estimate the population parameter
b. sample is used to estimate the population parameter
c. sample is used to estimate the sample statistic
d. None of the alternative ANSWERS is correct.
The following regression model has been proposed to predict sales at a furniture store.
= 10 – 4x1 + 7x2 + 18x3
where
x1 = competitor’s previous day’s sales (in $1,000s)
x2 = population within 1 mile (in 1000s)
x3 = 1 if any form of advertising was used, 0 if otherwise
= sales (in $1,000s)
If P(A) 0.80, P(B) 0.65, and P(A ˆ B) 0.78, then P(BA)
a. 0.6700
b. 0.8375
c. 0.9750
d. Not enough information is given to answer this question.
The probability distribution that can be described by just one parameter is the
a. uniform
b. normal
c. exponential
d. binomial