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QNT 275 QNT275

QNT 275 QNT275

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Tutorial

QNT/275
STATISTICS FOR DECISION MAKING
 
The Latest Version A+ Study Guide
 
**********************************************
QNT 275 Entire Course Link
https://uopcourses.com/category/qnt-275/
**********************************************
 
 
QNT 275 Week 1 Statistics in Business
Develop a 875-word response that addresses each of the following prompts:

Define statistics with citation and reference.

Contrast quantitative data and qualitative data. Use two Peer Reviewed references.

Evaluate tables and charts used to represent quantitative and qualitative data.

Describe the levels of data measurement.

Describe the role of statistics in business decision-making.

Provide at least two business research questions, or problem situations, in which statistics was used or could be used.

Use two peer reviewed references.
Format your assignment consistent with APA guidelines.
Click the Assignment Files tab to submit your assignment.
 
 
QNT 275 Week 1 Practice Set
Chapter 01, Section 1.3, Problem 008a
 
Correct.
 
Indicate if the following variable is quantitative or qualitative.
 
The amount of time a student spent studying for an exam is a
 
variable.
 
 
 
 
Chapter 01, Supplementary Exercises, Problem 043a
 
Correct.
 
State whether the following is an example of sampling with replacement or without replacement.
 
Selecting 60 patients out of 100 to test a new drug is sampling
 
replacement.
 
 
 
 
8th-ed Chapter 01, Section 1.2, Problem 006a
 
Correct.
 
Explain whether the following constitutes a population or a sample.
 
Opinions on a certain issue obtained from all adults living in a city constitute a
 
.
 
 
 
8th-ed Chapter 01, Section 1.3, Problem 009
The following table gives the number of dog bites reported to the police last year in six cities.
 
City Number of Bites
Center City   19
Elm Grove    38
Franklin 36
Bay City 33
Oakdale 38
Sand Point    53
 
With reference to this table, what is 38?
 
 
a measurement
 
a data set
 
a member
 
a variable
 
 
 
 
 
8th-ed Chapter 01, Section 1.3, Problem 011
 
Correct.
 
The following table gives the number of dog bites reported to the police last year in six cities.
City Number of Bites
Center City   46
Elm Grove    30
Franklin 51
Bay City 41
Oakdale 11
Sand Point    5

What is the variable for this data set?

 
The variable for this data set is the
 
.

How many observations are in this data set?

 
There is/are    observation(s) in this data set.

How many elements does this data set contain?

 
There is/are    element(s) in this data set.
 
 
 
 
 
8th-ed Chapter 01, Section 1.4, Problem 017
 
Correct.
 
Classify the following quantitative variable as discrete or continuous.
 
The amount of gasoline put into a car at a gas station is a
 
variable.
 
 
 
 
 
 
8th-ed Chapter 01, Section 1.6, Problem 021a
 
Correct.
 
Classify the following as cross-section or time-series data.
 
The average prices of houses in 500 cities is
 
data.
 
 
 
 
8th-ed Chapter 01, Section 1.7, Problem 023a
 
Correct.
 
The following table lists six pairs of m and f values.
m    5     4     23   11   11   19
f      15   10   16   7     3     13
Calculate the value of the following: ∑f=
exact number, no tolerance
 
 
 
 
 
 
 
8th-ed Chapter 01, Section 1.7, Problem 028a
 
Correct.
 
Nine randomly selected customers at a local fast-food restaurant ordered meals having the following calorie counts: 975, 520, 1560, 872, 1025, 431, 361, 502, and 1118. Let y denote the calorie content of a meal ordered at this restaurant. Find the following sum.
∑y=
exact number, no tolerance
 
 
QNT 275 Week 1 Quiz
Chapter 01, Testbank, Question 002
 
Your answer is correct.
 
Under inferential statistics, we study
 
 
 
how a sample is taken from a population
 
the methods to make decisions about one or more populations based on sample results
 
tables composed of summary measures
 
how to make decisions about a mean, median, or mode
 
 
 
 
Chapter 01, Testbank, Question 046
 
Your answer is correct.
 
Classify the variable as discrete or continuous.
 
Duration of your last 30 cell phone calls.
 
 
 
 
 
 
Chapter 01, Testbank, Question 048
 
Your answer is correct.
 
An independent group wants to determine if the consumption of gasoline has increased due to changes in price. The group randomly selects 320 gas stations from 12 different states and collects data from the month of the year when gas is the cheapest and from the month of the year when gas is the most expensive. The data shows no significant difference in gas consumption between the two months.
 
In this example, what is the variable being studied?
 
 
 
The 320 gas stations chosen.
 
The price of gasoline.
 
The consumption of gasoline.
 
The 12 different states.
 
 
 
Chapter 02, Testbank, Question 046-051
The following table gives the frequency distribution of the number of telephones owned by a sample of 50 households selected from a city.
Number of Telephones Owned       f
0     2
1     19
2     14
3     3
4     12
 
The relative frequency of the second class, rounded to two decimal places, is:
 
The number of households which own more than one telephone is:
 
The percentage of households which own three or more telephones is:
%
The number of households which own one or two telephones is:
 
The percentage of households which do not own a telephone is:
 
The number of classes for this frequency distribution table is:
 
 
 
Chapter 02, Section 2.2, Problem 012a
A data set on money spent on lottery tickets during the past year by 200 households has a lowest value of $1 and a highest value of $1640. Suppose we want to group these data into 6classes of equal widths.
Assuming we take the lower limit of the first class as $1 and the width of each class equal to $300, write the class limits for all six classes.
 
 
 
Number of Class Lower Limit  Upper Limit
1     1     300
2     301 600
3     601 900
4     901 1200
5     1201      1500
6     1501      1640
 
 
Number of Class Lower Limit  Upper Limit
1     1     299
2     300 599
3     600 899
4     900 1199
5     1200      1499
6     1500      1640
 
 
Number of Class Lower Limit  Upper Limit
1     1     299
2     300 599
3     600 899
4     900 1199
5     1200      1499
6     1500      1799
 
 
Number of Class Lower Limit  Upper Limit
1     1     300
2     300 600
3     600 900
4     900 1200
5     1200      1500
6     1500      1800
 
 
Number of Class Lower Limit  Upper Limit
1     1     300
2     301 600
3     601 900
4     901 1200
5     1201      1500
6     1501      1800
 
 
 
 
Chapter 02, Testbank, Question 090
The following table shows the countries whose teams have won the UEFA Champions League.
 
Country Frequency
Spain     12
England 11
Italy       11
Germany      6
Portugal       4
Other     10
 

a) Calculate the relative frequency of each country. Round your answers to three decimal places.

Spain:
England:
Italy:
Germany:
Netherlands:
Other:

b) Select the pie chart that better describes the data.

I   II   III
 
 
QNT 275 Week 2 Learning Team Charter Assignment
Develop a 150- to 200-word individual response to the following:
Consider the multiple definitions of collaboration.
Define collaboration and how you will apply it in this course based upon the discussion with your Learning Team. Be sure to reference and cite your sources.
Answer the question individually.
Click the Assignment Files tab to submit your assignment.
 
 
QNT 275 Week 2 Mini-Project 3-2
You are employed as a statistician for a company that makes household products, which are sold by part-time salespersons who work during their spare time. The company has four salespersons employed in a small town. Let us denote these salespersons by A, B, C, and D.
The sales records (in dollars) for the past 6 weeks for these four salespersons are shown in the table below.

Week
A
B
C
D
1
1774
2205
1330
1402
2
1808
1507
1295
1665
3
1890
2352
1502
1530
4
1932
1939
1104
1826
5
1855
2052
1189
1703
6
1726
1630
1441
1498

Your supervisor has asked you to prepare a brief report comparing the sales volumes and the consistency of sales of these four salespersons.
Use the mean sales for each salesperson to compare the sales volumes. 
Choose an appropriate statistical measure to compare the consistency of sales.
Make the calculations and write a 700-word report comparing the sales volumes and the consistency of sales of these four salespersons.
Format your assignment consistent with APA guidelines. 
Click the Assignment Files tab to submit your assignment.
 
 
QNT 275 Week 2 Practice Set
Chapter 03, Section 3.1, Problem 009
 
Correct.
 
The following data set belongs to a population:
4−220−1015127
 
Calculate the mean, median, and mode.
 
Round your answers to two decimal places if it is necessary.
 
Mean =
 
Median =
 
Mode =
 
 
 
 
 
 
 
Chapter 03, Section 3.2, Problem 033
 
Correct.
 
The following data give the prices of seven textbooks randomly selected from a university bookstore.
$85 $173      $105      $122      $51 $156      $141

Find the mean for these data. Calculate the deviations of the data values from the mean. Is the sum of these deviations zero?

Mean = $
Deviation from the mean for $173 = $
Sum of these deviations = $

Calculate the range, variance, and standard deviation. [Round your answers to 2 decimal places.]

Range = $
Variance =
Standard deviation = $
 
 
 
 
 
 
Chapter 03, Section 3.4, Problem 063
 
Your answer is correct.
 
The one-way commuting times from home to work for all employees working at a large company have a bell-shaped curve with a mean of 32 minutes and a standard deviation of 9 minutes. Using the empirical rule, find the approximate percentages of the employees at this company who have one-way commuting times in the following intervals.

5 to 59 minutes

 
%

23 to 41 minutes

 
%

14 to 50 minutes

 
%
 
 
 
 
 
 
Chapter 03, Section 3.5, Problem 069a
 
Correct.
 
The following data give the speeds of 13 cars, measured by radar, traveling on I-84.
 
73   75   69   68   78   69   74
77   72   83   63   77   71
 
Find the values of the three quartiles and the interquartile range.
 
Q1=
Q2=
Q3=
IQR= 8
 
 
 
 
Chapter 03, Section 3.6, Problem 077
 
Your answer is correct.
 
The following data give the 2015 bonuses (in thousands of dollars) of 15 randomly selected Wall Street managers.
107 122 163 95   48   347 75   273
60   786 127 203 402 239 71
Prepare a box-and-whisker plot.
 
 
QNT 275 Week 2 Quiz
Chapter 02, Section 2.1, Problem 006
The following data show the method of payment by 16 customers in a supermarket checkout line. Here, C refers to cash, C⁢K to check, C⁢C to credit card, and D to debit card, and O stands for other.
C     O    C⁢K       D     CC   D     D     C⁢K
C⁢C       C⁢C       D     C⁢C       C⁢C       O    O    O
 
 
 
 
 
 
Correct.
 

Prepare a frequency distribution table.

Category      Frequency
C
C⁢K
C⁢C
D
O
 
 
 
 
Chapter 02, Section 2.2, Problem 021
The following data give the number of turnovers (fumbles and interceptions) made by both teams in each of the football games played by North Carolina State University during the 2014 and 2015 seasons.
2     3     1     1     6     5     3     5     5     1     5     2     1
5     3     4     4     5     8     4     5     2     2     2     6
 
 
 
Correct.
 

Construct a frequency distribution table for these data using single-valued classes.

Calculate the relative frequency and percentage for each class.

 
Round your answers for relative frequencies to three decimal places and your answers for percentages to one decimal place.
 
Turnovers     Frequency    Relative Frequency    Percentage
1
 
 
2
 
 
3
 
 
4
 
 
5
 
 
6
 
 
7
 
 
8
 
 
 
 
 
 
Chapter 02, Section 2.3, Problem 027
 
Your answer is correct.
 
The following data give the times (in minutes) taken by 50 students to complete a statistics examination that was given a maximum time of 75 minutes to finish.
41   28   45   60   53   69   70   50   63   68
37   44   42   38   74   53   66   65   52   64
26   45   66   35   43   44   39   55   64   54
38   52   59   72   67   65   43   65   68   27
64   48   71   75   46   69   57   73   53   72

Prepare a stem-and-leaf display for these data. Arrange the leaves for each stem in increasing order. Type only digits (without spaces, commas, etc).

2
3
4
5
6
7

Prepare a split stem-and-leaf display for the data. Split each stem into two parts. The first part should contain the leaves 0, 1, 2, 3, and 4, and the second part should contains the leaves 5, 6, 7, 8, and 9. Type only digits (without spaces, commas, etc).

2
3
3
4
4
5
5
6
6
7
7

Which display (the one in part a or the one in part b) provides a better representation of the features of the distribution?

 
 
 
 
Chapter 02, Section 2.4, Problem 035
 
Your answer is correct.
 
The following data give the times (in minutes) taken by 50 students to complete a statistics examination that was given a maximum time of 75 minutes to finish.
41   28   45   59   53   69   70   51   63   68
37   44   42   38   74   53   66   65   52   64
26   45   66   34   43   44   39   55   64   54
38   52   58   72   67   65   43   65   68   27
64   50   71   75   45   69   56   73   53   72
Create a dotplot for these data.
 
 
 
 
 
 
Chapter 02, Section 2.2, Intelligent Tutoring Question 011
The following table gives the frequency distribution of the gallons of gasoline purchased by all customers on one day at a certain gas station.
 
 
Find a cumulative frequency distribution, the cumulative relative frequency and cumulative percentage for each class.
 
 
 
 
 
 
Chapter 02, Section 2.2, Intelligent Tutoring Question 011
 
 
Your answer is correct.
 
What is the cumulative frequency for “0 to less than 16” ?
 
Click if you would like to Show Work for this question:     Open Show Work
 
 
 
 
LINK TO TEXT
 
Attempts: 1 of 3 used
 
 
 
 
 
 
 
Chapter 02, Section 2.2, Intelligent Tutoring Question 011
 
 
Your answer is correct.
 
Find the cumulative relative frequency for “0 to less than 12”.
 
 
Round answer to three decimal places.
Click if you would like to Show Work for this question:     Open Show Work
 
 
 
 
LINK TO TEXT
 
Attempts: 1 of 3 used
 
 
 
 
 
 
 
Chapter 02, Section 2.2, Intelligent Tutoring Question 011
 
 
Your answer is correct.
 
What is the cumulative percentage for “0 to less than 20”?
 
%
Round answer to one decimal place.
Click if you would like to Show Work for this question:     Open Show Work
 
 
 
 
LINK TO TEXT
 
Attempts: 1 of 3 used
 
 
 
 
 
Chapter 02, Section 2.2, Intelligent Tutoring Question 011
 
 
Your answer is correct.
 
Using similar calculations to the steps above, find the percentage of customers who purchased less than 8 gallons.
 
%
Round answer to one decimal place.
Click if you would like to Show Work for this question:     Open Show Work
 
 
 
 
Chapter 02, Section 2.1, Additional Question 005
 
Correct.
 
Use the following data to construct a frequency table, using classes of [60, 65), [65, 70), etc.
86   90   79   82   86   95   91   90
88   92   93   80   92   95   64   90
Frequency table:
Class Interval      Frequency
[60, 65)
[65, 70)
[70, 75)
[75, 80)
[80, 85)
[85, 90)
[90, 95)
[95, 100)
 
 
 
Chapter 02, Testbank, Question 092
 
Correct.
 
Find the histogram that better describes the data.
Value x  Frequency    Relative Frequency
1     5     0.28
2     2     0.11
3     4     0.22
4     4     0.22
5     3     0.17
Total      18   1.000
 
 
I      II     III
 
 
 
 
Chapter 03, Section 3.1, Problem 009
 
Correct.
 
The following data set belongs to a population:
5−430−914129
 
Calculate the mean, median, and mode.
 
Round your answers to two decimal places if it is necessary.
 
Mean =
 
Median =
 
Mode =
 
 
 
Chapter 03, Section 3.1, Problem 025
 
Correct.
 
The mean age of six persons is 48 years. The ages of five of these six persons are 62, 40, 36, 46, and 44 years.
 
Find the age of the sixth person.
 
years
 
exact number, no tolerance
 
Chapter 03, Section 3.3, Problem 048
 
Your answer is partially correct.
 
Using the sample formulas, find the mean, variance, and standard deviation for the grouped data displayed in the following table.
x     f
0 to less than 4    19
4 to less than 8    21
8 to less than 12  16
12 to less than 16       12
16 to less than 20       7
20 to less than 24       5
Carry out all calculations exactly, round to 2 decimal places the final answers only.
Mean =
Variance =
Standard deviation =
 
 
 
QNT 275 Week 3 Business Decision Making Project Part 1
Identify a business problem or opportunity at a company where you work or with which you’re familiar. This will be a business problem that you use for the individual assignments in Weeks 3 to 5. It should be a problem/opportunity for which gathering and analyzing some type of data would help you understand the problem/opportunity better.
Identify a research variable within the problem/opportunity that could be measured with some type of data collection.
Consider methods for collecting a suitable sample of either qualitative or quantitative data for the variable.
Consider how you will know if the data collection method would be valid and reliable.
Develop a 1,050-word analysis to describe a company, problem, and variable.
Include in your submission:

Identify the name and description of the selected company.

Describe the problem at that company.

Identify one research variable from that problem.

Describe the methods you would use for collecting a suitable sample of either qualitative or quantitative data for the variable (Note: do not actually collect any data).

Analyze how you will know if the data collection method would generate valid and reliable data (Note: do not actually collect any data).

Format your assignment consistent with APA guidelines. 
Click the Assignment Files tab to submit your assignment.
 
 
QNT 275 Week 3 Practice Set
Chapter 04, Section 4.1, Problem 009a
 
 
Correct.
 
In a group of adults, some own iPads, and others do not. Indicate whether the following is a simple or a compound event. Assume two persons are selected randomly.
 
One person has an iPad and the other does not.
 
 
 
 
 
Chapter 04, Section 4.1, Problem 009b
 
 
Correct.
 
In a group of adults, some own iPads, and others do not. Indicate whether the following is a simple or a compound event. Assume two persons are selected randomly.
 
At least one person has an iPad.
 
 
 
 
 
 
Chapter 04, Section 4.1, Problem 009c
 
 
Correct.
 
In a group of adults, some own iPads, and others do not. Indicate whether the following is a simple or a compound event. Assume two persons are selected randomly.
 
Not more than one person has an iPad.
 
 
 
 
 
 
Chapter 04, Section 4.1, Problem 009d
 
 
Correct.
 
In a group of adults, some own iPads, and others do not. Indicate whether the following is a simple or a compound event. Assume two persons are selected randomly.
 
The first person has an iPad and the second does not.
 
 
 
 
 
 
Chapter 04, Section 4.2, Problem 021
 
 
Correct.
 
A random sample of 1605 adults showed that 632 of them have shopped at least once on the Internet. What is the (approximate) probability that a randomly selected adult has shopped on the Internet?
Round your answer to three decimal places.
 
the tolerance is +/-2%
 
 
 
 
Chapter 04, Section 4.3, Problem 036
 
 
Your answer is correct.
 
Six hundred adults were asked whether or not they watch for calories and fat content when they buy groceries. The following table gives the two-way classification of their responses, where yes means that an adult watches for calories and fat content and no means he/she does not watch.
Yes  No   No Opinion
Men       75   169 56
Women  104 126 70
Give exact answers in fraction form.

If one adult is randomly selected from these 600 adults, find the probability that this adult

is a man

Probability =
 

does not watch for calories and fat content

Probability =
 
iii. watches for calories and fat content given that this adult is a woman
Probability =
 

is a man given that this adult has no opinion

Probability =
 

Are events men and yes mutually exclusive?

 
What about yes and no opinion?
 

Are events men and no independent?

 
 
 
 
Chapter 05, Section 5.2, Problem 07d
 
 
Correct.
 
The following table gives the probability distribution of a discrete random variable x.
x     0     1     2     3     4     5     6
P(x) 0.12       0.18       0.28       0.15       0.12       0.07       0.08
Find P(1≤x≤4).
P(1≤x≤4)=
exact number, no tolerance
 
 
 
 
Chapter 05, Section 5.3, Problem 021
 
 
Correct.
 
The H2 Hummer limousine has eight tires on it. A fleet of 1214 H2 limos was fit with a batch of tires that mistakenly passed quality testing. The following table lists the frequency distribution of the number of defective tires on the 1214 H2 limos.
 
Number of defective tires       0     1     2     3     4     5     6     7     8
Number of H2 limos  55   209 347 301 203 75   17   4     3
 
Construct a probability distribution table for the numbers of defective tires on these limos.
 
Round your answers to three decimal places.
 
x     P(x)
0
1
2
3
4
5
6
7
8
 
Calculate the mean and standard deviation for the probability distribution you developed for the number of defective tires on all 1214 H2 Hummer limousines.
Round your answers to three decimal places.
 
There is an average of    defective tires per limo, with a standard deviation of    tires.
 
 
QNT 275 Week 3 Quiz
Chapter 04, Section 4.2, Problem 015
Which of the following values cannot be probabilities of events?
 
15   0.94       -0.55      1.57       53   0.0  -27  1.0
 
 
Select all that apply.
 
 
 
-27
 
53
 
0.0
 
1.0
 
15
 
0.94
 
-0.55
 
1.57
 
 
 
 
Chapter 04, Section 4.2, Problem 017
The president of a company has a hunch that there is a 0.30 probability that the company will be successful in marketing a new brand of ice cream. Is this a case of classical, relative frequency, or subjective probability?
 
 
 
Relative frequency probability
 
Subjective probability
 
Classical probability
 
 
 
 
 
Chapter 04, Section 4.2, Problem 020
 
 
Correct.
 
A regular, six-sided die is rolled once.
 
Round your answers to four decimal places.
 

What is the probability that a number less than 3 is obtained?

 
P(a number less than 3 is obtained)=

What is the probability that a number 2 to 5 is obtained?

 
P(a number 2 to 5 is obtained)=
 
 
 
 
Chapter 04, Section 4.2, Problem 021
 
 
Correct.
 
A random sample of 1115 adults showed that 539 of them have shopped at least once on the Internet. What is the (approximate) probability that a randomly selected adult has shopped on the Internet?
Round your answer to three decimal places.
 
the tolerance is +/-5%
 
 
 
 
Chapter 05, Section 5.1, Problem 002a
 
 
Correct.
 
Classify the following random variable as discrete or continuous.
The time left on a parking meter.
 
 
 
 
 
Chapter 05, Section 5.1, Problem 002b
 
 
Correct.
 
Classify the following random variable as discrete or continuous.
The number of bats broken by a major league baseball team in a season.
 
 
 
 
 
Chapter 05, Section 5.2, Problem 07b
 
 
Correct.
 
The following table gives the probability distribution of a discrete random variable x.
x     0     1     2     3     4     5     6
P(x) 0.12       0.19       0.30       0.15       0.11       0.09       0.04
Find P(x≤2).
P(x≤2)=
exact number, no tolerance
 
 
 
 
Chapter 05, Section 5.4, Problem 029
Select each of the following experiments that are binomial experiments.
 
 
 
Drawing 3 balls with replacement from a box that contains 13 balls, 6 of which are red and7 are blue, and observing the colors of the drawn balls.
 
Selecting a few households from New York City and observing whether or not they own stocks when it is known that 30% of all households in New York City own stocks.
 
Drawing 3 balls without replacement from a box that contains 13 balls, 6 of which are red and 7 are blue, and observing the colors of the drawn balls.
 
 
 
 
 
Chapter 04, Section 4.2, Problem 019
 
 
Correct.
 
A hat contains 30 marbles. Of them, 17 are red and 13 are green. If one marble is randomly selected out of this hat, what is the probability that this marble is green?
 
Round your answer to two decimal places.
 
P(A)=
the tolerance is +/-5%
 
 
 
 
 
8th-ed Chapter 04, Section 4.3, Problem 046a
 
 
Correct.
 
A statistical experiment has eight equally likely outcomes that are denoted by 1,2,3,4,5,6,7, and 8. Let event A= and event B=.
 
The events A and B
 
mutually exclusive events.
 
 
 
QNT 275 Week 4 Business Decision Making Project Part 2
Use the same business problem/opportunity and research variable you wrote about in Week 3. 
Remember: Do not actually collect any data; think hypothetically.
Develop a 1,050-word report in which you:

Identify the types of descriptive statistics that might be best for summarizing the data, if you were to collect a sample.

Analyze the types of inferential statistics that might be best for analyzing the data, if you were to collect a sample.

Analyze the role probability or trend analysis might play in helping address the business problem.

Analyze the role that linear regression for trend analysis might play in helping address the business problem.

Analyze the role that a time series might play in helping address the business problem.

Format your assignment consistent with APA guidelines.
Click the Assignment Files tab to submit your assignment.
 
 
QNT 275 Week 4 Practice Set
Chapter 06, Section 6.1, Problem 013
 
 
Correct.
 
Find the area under the standard normal curve between z=-1.53 and z=2.37.
Round your answer to four decimal places.
 
 
A=
the tolerance is +/-2%
 
 
 
 
 
Chapter 06, Section 6.1, Problem 015a
 
 
Correct.
 
Obtain the area under the standard normal curve to the right of z=1.37.
 
Round your answer to four decimal places.
A=
the tolerance is +/-2%
 
 
 
Chapter 06, Section 6.2, Problem 019a
 
 
Correct.
 
Find the z value for x=33 for a normal distribution with μ=30 and σ=5.
Enter the exact answer.
z=
exact number, no tolerance
 
 
 
Chapter 06, Section 6.2, Intelligent Tutoring Problem 023
Compute probabilities.
 
Recall the following definitions from section 6.4 of the text.
The area under the normal curve from x = a to x = b with given mean and standard deviation is the probability that x assumes a value between x = a and x = b. If we are using Table IV in Appendix C, we need to standardize the random variable x using the formula z = (x− µ)/σ, before using the table.
Alternatively, you may use a graphing calculator to obtain more accurate calculations without standardizing the random variable x.
For example, using a TI83 plus we calculate the area under the normal curve from x = a to x = b by using the
normalcdf(a,b,µ,σ)
where µ is the mean and σ is the standard deviation of the normal distribution. We use 1E99 for ∞ and −1E99 for −∞, if needed.
 
 
 
 
 
Chapter 06, Section 6.2, Intelligent Tutoring Problem 023
 
 
 
Your answer is correct.
 
Let x be a continuous random variable that is normally distributed with a mean of 24 and a standard deviation of 5.
Round your answers to two decimal places.
(a) Standardize the variable value x = 26.9.
z =
(b) Standardize the variable value x = 49.0.
z =
 
 
 
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Chapter 06, Section 6.2, Intelligent Tutoring Problem 023
 
 
 
Your answer is correct.
 
Let x be a continuous random variable that is normally distributed with a mean of 24 and a standard deviation of 5.
(a) Write a cumulative probability statement for the area under the normal curve to find the probability that x assumes a value between 26.9 and 49.0:
 
(b) Write an equivalent standardized probability statement for (a) above using the results obtained in the previous step:
 
 
 
 
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Attempts: 1 of 3 used
 
 
 
 
 
Chapter 06, Section 6.2, Intelligent Tutoring Problem 023
 
 
 
Your answer is correct.
 
Compute the following probability. Round your answer to four decimal places.
Area under normal curve between x = 26.9 and x = 49.0 is given by
P(26.9 < x < 49.0) = P( 0.58 < z < 5) =
the tolerance is +/-2%
 
 
 
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Attempts: 1 of 3 used
 
 
 
 
 
Chapter 06, Section 6.2, Intelligent Tutoring Problem 023
 
 
 
Your answer is correct.
 
Now, if the mean is 26 and the standard deviation is 6, find the probability that x assumes a value between 29.5 and 56.0.
Round your answer to four decimal places.
The probability =
the tolerance is +/-2%
 
 
 
 
Chapter 07, Section 7.1, Video Quiz 1
 
 
Your answer is correct.
 
Please view the following video before answering this question. Distribution of the Sample Mean
The 5 ages of the population have one mean. However, when looking at the 10 samples of 3 of those means, there are 10 means – one for each sample. State the symbols for the one mean and then the 10 means.
 
 
 
µ,  x¯.
 
x¯,  x¯.
 
x¯, µ.
 
µ, µ.
 
 
QNT 275 Week 4 Quiz
Chapter 06, Testbank, Question 001
 
 
Your answer is correct.
 
A continuous random variable is a random variable that can:
 
 
 
assume no continuous random frequency
 
assume any value in one or more intervals
 
have no random sample
 
assume only a countable set of values
 
 
Chapter 06, Testbank, Question 009
 
 
Your answer is correct.
 
Which of the following is not a characteristic of the normal distribution?
 
 
 
The value of the mean is always greater than the value of the standard deviation
 
The curve is symmetric about the mean
 
The two tails of the curve extend indefinitely
 
The total area under the curve is 1.0
 
 
Chapter 06, Testbank, Question 010
 
 
Your answer is correct.
 
The total area under a normal distribution curve to the left of the mean is always:
 
 
 
greater than .5
 
equal to zero
 
equal to 1
 
equal to 0.5
 
 
Chapter 06, Testbank, Question 015
 
 
Your answer is correct.
 
For the standard normal distribution, the mean is:
 
 
 
1 and the standard deviation is 1
 
0.5 and the standard deviation is 0.5
 
1 and the standard deviation is zero
 
zero and the standard deviation is 1
 
 
Chapter 06, Testbank, Question 020
 
 
Your answer is correct.
 
For the standard normal distribution, the area between z = 0 and z = 2.94, rounded to four decimal places, is:
 
the tolerance is +/-2%
 
Chapter 06, Testbank, Question 023
 
 
Your answer is correct.
 
For the standard normal distribution, the area to the right of z = -2.12, rounded to four decimal places, is:
 
the tolerance is +/-2%
 
 
Chapter 06, Testbank, Question 026
 
 
Your answer is correct.
 
For the standard normal distribution, the area between z = 0.24 and z = 1.03, rounded to four decimal places, is:
 
the tolerance is +/-2%
 
 
Chapter 06, Testbank, Question 033-035
The GMAT scores of all examinees who took that test this year produce a distribution that is approximately normal with a mean of 420 and a standard deviation of 34.
The probability that the score of a randomly selected examinee is between 400 and 480, rounded to four decimal places, is:
The probability that the score of a randomly selected examinee is less than 370, rounded to four decimal places, is:
The probability that the score of a randomly selected examinee is more than 530, rounded to four decimal places, is:
 
 
 
QNT 275 Week 5 Business Decision Making Project Part 3
Prepare an 11- to 15-slide Microsoft® PowerPoint® presentation for the senior management team based on the business problem or opportunity you described in Weeks 3 and 4.
Include on the slides what you would want the audience to see (include appropriate visual aids/layout). In the Speaker Notes section, include what you would say as you present each slide. If any source material is quoted or paraphrased in the presentation, use APA citations and references.
Draw on material you developed in the Week 3 and 4 assignments.
Include the following in your presentation:

Introduction slide

Agenda slide

Describe the organization, with a brief description

Explain the business problem or opportunity

Analyze why the business problem is important

Identify what variable would be best to measure for this problem and explain why

Apply data analysis techniques to this problem (tell which techniques should be used: descriptive stats, inferential stats, probability, time series) and explain why

Apply a possible solution to the problem/opportunity, with rationale

Evaluate how data could be used to measure the implementation of such a solution

Conclusion

References slide (if any source material is quoted or paraphrased throughout the presentation)

Format your assignment consistent with APA guidelines. 
Click the Assignment Files tab to submit your assignment.
 
 
QNT 275 Week 5 Quiz
Chapter 08, Section 8.2, Problem 010
 
Correct.
 
Find  z for a  90% confidence level.
 
Round your answer to two decimal places.
 
z=
the tolerance is +/-2%
 
 
 
 
 
 
 
Chapter 08, Section 8.2, Problem 011
 
Your answer is partially correct.
 
For a data set obtained from a sample, n=80 and x¯=46.55. It is known that σ=3.9.
 

What is the point estimate of μ?

 
The point estimate is   .
 

Make a 97% confidence interval for μ.

 
Round your answers to two decimal places.
 
(  ,  )
 

What is the margin of error of estimate for part b?

 
Round your answer to three decimal places.
 
E=
 
 
 
Chapter 08, Section 8.2, Problem 017a
 
Correct.
 
Determine the sample size for the estimate of μ for the following.
E=2.4, σ=12.35, confidence level=99%.
 
Round your answer to the nearest integer.
n=
the tolerance is +/-2%
 
 
 
 
 
Chapter 08, Section 8.3, Problem 034b
 
Correct.
 
For the following, find the area in the appropriate tail of the t distribution.
t=1.711 and n=25.
Round your answer to 3 decimal places.
 
Area in the
 
tail is
the tolerance is +/-2%
 
 
 
 
 
Chapter 09, Section 9.1, Problem 004a
 
Correct.
 
Which of the following is a left-tailed test?
 
 
 
H0: μ=101, H1: μ<101
 
H0: μ=48, H1: μ≠48
 
H0: μ=73, H1: μ>73
 
 
 
 
Chapter 09, Section 9.1, Problem 007
 
Correct.
 
Write the null and alternative hypotheses for the following example. Determine if the example is a case of a two-tailed, a left-tailed, or a right-tailed test.
To test if the mean length of experience of airport security guards is different from 3 years.
 
 
 
≠H0: μ≠3 years, H1: μ=3 years, right-tailed test
 
H0: μ=3 years, ≠H1: μ≠3 years, two-tailed test
 
H0: μ=3 years, H1: μ<3 years, left-tailed test
 
H0: μ=3 years, H1: μ>3 years, right-tailed test
 
≤H0: μ≤3 years, H1: μ>3 years, two-tailed test
 
 
 
 
 
 
Chapter 09, Section 9.2, Problem 014c
 
Correct.
 
Consider H0: μ=38 versus H1: μ>38. A random sample of 35 observations taken from this population produced a sample mean of 40.26. The population is normally distributed with σ=7.2.
Calculate the p-value. Round your answer to four decimal places.
p=
the tolerance is +/-2%
 
 
 
 
Chapter 09, Section 9.2, Problem 020a
 
Correct.
 
A random sample of 125 observations produced a sample mean of 31. Find the critical and observed values of z for the following test of hypothesis using α=0.01. The population standard deviation is known to be 5 and the population distribution is normal.
H0: μ=28 versus H1: μ≠28.
Round your answers to two decimal places.
zcritical left =
zcritical right =
zobserved =
 
 
 
 
 
 
 
Chapter 09, Section 9.2, Problem 025b
 
Correct.
 
The manufacturer of a certain brand of auto batteries claims that the mean life of these batteries is 45 months. A consumer protection agency that wants to check this claim took a random sample of 24 such batteries and found that the mean life for this sample is 43.05 months. The lives of all such batteries have a normal distribution with the population standard deviation of 4.5 months.
Test the hypothesis H0: μ=45 months versus H1: μ<45 months using the critical-value approach and α=0.1.
H0 is
 
 
 
Chapter 01, Section 1.3, Video Quiz 2
 
Your answer is correct.
 
Please view the following video before answering this question. Soda with Callouts
The number of sodas is what type of data?
 
 
 
Discrete.
 
Continuous.
 
 
QNT 275 Week 5 Final Exam
Chapter 01, Testbank, Question 012
Your answer is correct.
A quantitative variable is the only type of variable that can:
have no intermediate values
assume numeric values for which arithmetic operations make sense
be graphed
be used to prepare tables
Chapter 01, Testbank, Question 015
Your answer is correct.
A qualitative variable is the only type of variable that:
can assume numerical values
cannot be graphed
can assume an uncountable set of values
cannot be measured numerically
Chapter 02, Testbank, Question 067-072
Correct.
The following table gives the cumulative frequency distribution of the commuting time (in minutes) from home to work for a sample of 400 persons selected from a city.
Time (minutes)   f
0 to less than 10  66
0 to less than 20  148
0 to less than 30  220
0 to less than 40  294
0 to less than 50  356
0 to less than 60  400
The sample size is:
The percentage of persons who commute for less than 30 minutes, rounded to two decimal places, is:
%
The cumulative relative frequency of the fourth class, rounded to four decimal places, is:
The percentage of persons who commute for 40 or more minutes, rounded to two decimal places, is:
%
The percentage of persons who commute for less than 50 minutes, rounded to two decimal places, is:
%
The number of persons who commute for 20 or more minutes is:
Chapter 03, Testbank, Question 027-029
The temperatures (in degrees Fahrenheit) observed during seven days of summer in Los Angeles are:
78,99,68,91,97,75,85
The range of these temperatures is:
The variance of these temperatures, rounded to three decimals, is:
The standard deviation, rounded to three decimals, of these temperatures is:
Chapter 04, Testbank, Question 021-026
Your answer is  correct.
The following table gives the two-way classification of 500 students based on sex and whether or not they suffer from math anxiety.
Suffer From Math Anxiety
Sex  Yes  No
Male      151 89
Female  184 76
If you randomly select one student from these 500 students, the probability that this selected student is a female is:   (round your answer to three decimal places, so 0.0857 would be 0.086)
If you randomly select one student from these 500 students, the probability that this selected student suffers from math anxiety is:   (round your answer to three decimal places, so 0.0857 would be 0.086)
If you randomly select one student from these 500 students, the probability that this selected student suffers from math anxiety, given that he is a male is:   (round your answer to three decimal places, so 0.0857 would be 0.086)
If you randomly select one student from these 500 students, the probability that this selected student is a female, given that she does not suffer from math anxiety is:   (round your answer to three decimal places, so 0.0857 would be 0.086)
Which of the following pairs of events are mutually exclusive?
Male and no
No and yes
Male and yes
Female and yes
Female and male
Female and no
Are the events “Has math anxiety” and “Person is female” independent or dependent? Detail the calculations you performed to determine this.
Chapter 05, Testbank, Question 009
Your answer is correct.
For the probability distribution of a discrete random variable x, the sum of the probabilities of all values of x must be:
equal to 1
equal to zero
in the range zero to 1
equal to 0.5
Chapter 05, Testbank, Question 034-035
Your answer is correct.
The following table lists the probability distribution of a discrete random variable x:
x     2     3     4     5     6     7     8
P(x) 0.15       0.3  0.24       0.13       0.1  0.06       0.02
The mean of the random variable x is:
The standard deviation of the random variable x, rounded to three decimal places, is:
Chapter 06, Testbank, Question 036-038
The daily sales at a convenience store produce a distribution that is approximately normal with a mean of 1270 and a standard deviation of 136.
The probability that the sales on a given day at this store are more than
1,405, rounded to four decimal places, is:
The probability that the sales on a given day at this store are less than
1,305, rounded to four decimal places, is:
The probability that the sales on a given day at this store are between
1,200 and 1,300, rounded to four decimal places, is:
Chapter 08, Testbank, Question 010
Your answer is correct.
The width of a confidence interval depends on the size of the:
population mean
margin of error
sample mean
none of these
Chapter 08, Testbank, Question 014
Your answer is correct.
A sample of size 67 from a population having standard deviation
= 41 produced a mean of 248.00. The 95% confidence interval for the population mean (rounded to two decimal places) is:
The lower limit is
The upper limit is
Chapter 09, Testbank, Question 001
The null hypothesis is a claim about a:
population parameter, where the claim is assumed to be true until it is declared false
population parameter, where the claim is assumed to be false until it is declared true
statistic, where the claim is assumed to be false until it is declared true
statistic, where the claim is assumed to be true until it is declared false
Chapter 09, Testbank, Question 002
Your answer is correct.
The alternative hypothesis is a claim about a:
statistic, where the claim is assumed to be true if the null hypothesis is declared false
population parameter, where the claim is assumed to be true if the null hypothesis is declared false
statistic, where the claim is assumed to be false until it is declared true
population parameter, where the claim is assumed to be true until it is declared false
Chapter 09, Testbank, Question 003
Your answer is correct.
In a one-tailed hypothesis test, a critical point is a point that divides the area under the sampling distribution of a:
statistic into one rejection region and one nonrejection region
population parameter into one rejection region and one nonrejection region
statistic into one rejection region and two nonrejection regions
population parameter into two rejection regions and one nonrejection region
Chapter 09, Testbank, Question 004
Your answer is correct.
In a two-tailed hypothesis test, the two critical points are the points that divide the area under the sampling distribution of a:
statistic into two rejection regions and one nonrejection region
statistic into one rejection region and two nonrejection regions
population parameter into two rejection regions and one nonrejection region
population parameter into one rejection region and one nonrejection region
Chapter 09, Testbank, Question 005
Your answer is correct.
In a hypothesis test, a Type I error occurs when:
a true null hypothesis is rejected
a false null hypothesis is rejected
a false null hypothesis is not rejected
a true null hypothesis is not rejected
Chapter 09, Testbank, Question 006
Correct answer.   Your answer is correct.
In a hypothesis test, a Type II error occurs when:
Entry field with correct answer
a false null hypothesis is not rejected
a true null hypothesis is rejected
a true null hypothesis is not rejected
a false null hypothesis is rejected
Chapter 09, Testbank, Question 007
Correct answer.   Your answer is correct.
In a hypothesis test, the probability of committing a Type I error is called the:
Entry field with correct answer
confidence interval
significance level
beta error
confidence level