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Part 1 of 16 -
1.0 Points
Question 1 of 23
The data presented in the table below resulted from an experiment in which seeds of 5 different types were
planted and the number of seeds that germinated within 5 weeks after planting was recorded for each
seed type. At the .01 level of significance, is the proportion of seeds that germinate dependent on the
seed type?
Observed Frequencies
Germinated
Failed to Germinate
1
31
7
2
57
33
3
87
60
4
52
44
5
10
19
Seed Type
A.Yes, because the test value 16.86 is greater than the critical value of 13.28
B.Yes, because the test value 16.86 is less than the critical value of 14.86
C.No, because the test value 16.86 is greater than the critical value of 13.28
D.No, because the test value 13.28 is less than the critical value of 16.86
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Question 2 of 23
The chi-square goodness-of-fit test can be used to test for:
A.significance of sample statistics
B.normality
C.difference between population variances
D.difference between population means
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Part 2 of 16 -
1.0 Points
1.0 Points
Question 3 of 23
The marketing manager of a large supermarket chain would like to use shelf space to predict the sales of
pet food. For a random sample of 12 similar stores, she gathered the following information regarding the
shelf space, in feet, devoted to pet food and the weekly sales in hundreds of dollars.
Store
1
2
3
4
5
6
Shelf Space
5
5
5
10
10
10
1.6
2.2
1.4
1.9
2.4
2.6
Store
7
8
9
10
11
12
Shelf Space
15
15
15
20
20
20
Weekly Sales
2.3
2.7
2.8
2.6
2.9
3.1
Weekly Sales
What is the estimated regression equation?
A.
= 1.45 + 0.074x
B.
= 2.63 - 0.174x
C.
= 2.63 + 0.724x
D.
= 1.45 + 0.724x
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Question 4 of 23
1.0 Points
A single variable X can explain a large percentage of the variation in some other variable Y when the two
variables are:
A.highly correlated
B.directly related
C.inversely related
D.mutually exclusive
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1.0 Points
Question 5 of 23
Data for a sample of 25 apartments in a particular neighborhood are provided in the worksheet
Apartments in the Excel workbook Apartments.xlsx. Using that data, find the estimated regression
equation which can be used to estimate the monthly rent for apartments in this neighborhood using size
as the predictor variable.
Apartments.xlsx
A.
177.12 + 1.065(size)
B.
177.12 + 0.8500(size)
C.
1.065 + 177.12(size)
D.
197.12 + 2.065(size)
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Part 3 of 16 -
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Question 6 of 23
A pharmaceutical company is testing the effectiveness of a new drug for lowering cholesterol. As part of
this trial, they wish to determine whether there is a difference between the effectiveness for women and
for men. Assume α = 0.05. What is the test value?
Women
Men
Sample size
50
80
Mean effect
7
6.95
Sample variance
3
4
A.t = 3.252
B.t = 0.151
C.z = 0.081
D.z = 0.455
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Question 7 of 23
1.0 Points
Members of the general adult population volunteer an average of 4.2 hours per week. A random sample of 20
female college students and 18 male college students produced the results given in the table below. At
the .01 level of significance, is there sufficient evidence to conclude that a difference exists between the
mean number of volunteer hours per week for male and female college students?
Females
Males
Sample size
20
18
Sample mean
3.8
2.5
Sample variance
3.5
2.2
A.No, because the test value 2.38 is greater than the critical value
B.No, because the test value 2.38 does not exceed the critical value
C.No, because the test value 2.90 is greater than the critical value
D.Yes, because the test value 2.90 is greater than the critical value
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Part 4 of 16 -
Question 8 of 23
1.0 Points
A type II error occurs when:
A.the sample mean differs from the population mean
B.the null hypothesis is incorrectly accepted when it is false
C.the null hypothesis is incorrectly rejected when it is true
D.the test is biased
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Question 9 of 23
1.0 Points
Suppose that the mean time for a certain car to go from 0 to 60 miles per hour was 7.7 seconds.
Suppose that you want to test the claim that the average time to accelerate from 0 to 60 miles per hour is
longer than 7.7 seconds. What would you use for the alternative hypothesis?
A.H1:
B.H1:
< 7.7 seconds
7.7 seconds
C.H1:
> 7.7 seconds
D.H1:
= 7.7 seconds
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Question 10 of 23
In an article appearing in Today’s Health a writer states that the average number of calories in a serving
of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from
75, a nutritionist selected a random sample of 20 servings of popcorn and computed the sample mean
number of calories per serving to be 78 with a sample standard deviation of 7.
State the null and alternative hypotheses.
A.H0:
= 75, H1:
> 75
B.H0:
= 75, H1:
≠ 75
C.H0:
75, H1:
> 75
D.H0:
75, H1:
< 75
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Part 5 of 16 -
Question 11 of 23
1.0 Points
A previous study of nickels showed that the standard deviation of the weight of nickels is 150 milligrams.
How many nickels does a coin counter manufacturer need to weigh so that she can be 98% confident
that her sample mean is within 25 milligrams of the true average weight of a nickel?
A.36
B.196
C.239
D.139
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Question 12 of 23
1.0 Points
A sample of 23 European countries found that the variance of life expectancy was 7.3 years. What is the
95% confidence interval estimate for the variance of life expectancy in Europe?
A.27.2 <
< 118.3
B.5.6 <
< 10.3
C.4.4 <
< 14.6
D.28.9 <
< 115.0
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Part 6 of 16 -
Question 13 of 23
1.0 Points
Given that the random variable X is normally distributed with a mean of 80 and a standard deviation of
10, P(85 < X < 90) is
A.0.1915
B.0.1498
C.0.3413
D.0.5328
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Part 7 of 16 -
Question 14 of 23
1.0 Points
Suppose that 50 identical batteries are being tested. After 8 hours of continuous use, assume that a
given battery is still operating with a probability of 0.70 and has failed with a probability of 0.30.
What is the probability that between 25 and 30 batteries (inclusive) will last at least 8 hours?
A.0.7792
B.0.0839
C.0.1186
D.0.9169
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Part 8 of 16 -
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Question 15 of 23
If two events are independent, what is the probability that they both occur?
A.0.0
B.0.5
C.1.00
D.Cannot be determined from the information given
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Part 9 of 16 -
3.0 Points
Question 16 of 23
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces
(e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific
notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
A sport preference poll yielded the following data for men and women. Use a 5% significance level and
test to determine if sport preference and gender are independent.
Sport Preferences of Men and Women
Basketball Football Soccer
Men
20
25
30
75
Women
18
12
15
45
38
37
45
120
What is the test value for this hypothesis test?
Answer:
Round your answer to two decimal places.
What is the critical value for this hypothesis test?
Answer:
Round your answer to two decimal places.
What is the conclusion for this hypothesis test? Choose one.
1. There is sufficient evidence to support the claim that one's sport preference is dependent on one's
gender.
2. There is not sufficient evidence to support the claim that one's sport preference is dependent on one's
gender.
Answer:
Enter only a 1 or 2 for your answer.
Part 10 of 16 -
1.0 Points
Question 17 of 23
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces
(e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific
notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
The marketing manager of a large supermarket chain would like to determine the effect of shelf space (in
feet) on the weekly sales of international food (in hundreds of dollars). A random sample of 12 equal –
sized stores is selected, with the following results:
Store
Shelf Space(X)
Weekly Sales(Y)
1
10
2.0
2
10
2.6
3
10
1.8
4
15
2.3
5
15
2.8
6
15
3.0
7
20
2.7
8
20
3.1
9
20
3.2
10
25
3.0
11
25
3.3
12
25
3.5
Find the equation of the regression line for these data. What is the value of the standard error of the
estimate? Place your answer, rounded to 3 decimal places, in the blank. Do not use a dollar sign. For
example, 0.345 would be a legitimate entry.
Part 11 of 16 -
Question 18 of 23
1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces
(e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific
notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
An investor wants to compare the risks associated with two different stocks. One way to measure the risk
of a given stock is to measure the variation in the stock’s daily price changes.
In an effort to test the claim that the variance in the daily stock price changes for stock 1 is different from
the variance in the daily stock price changes for stock 2, the investor obtains a random sample of 21
daily price changes for stock 1 and 21 daily price changes for stock 2.
The summary statistics associated with these samples are: n1 = 21, s1 = .848, n2 = 21, s2 = .529.
If you follow Bluman's advice and place the larger variance in the numerator when computing the test
value, at the .05 level of significance, what is the critical value associated with this test of hypothesis?
Place your answer, rounded to 2 decimal places, in the blank. For example, 3.45 would be a legitimate
entry.
Part 12 of 16 -
1.0 Points
Question 19 of 23
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces
(e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific
notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
The mean weight of loads of coal placed in train cars by a loading machine is 43.0 tons with a standard
deviation of 8.0 tons. Assuming that the weight of loads placed in the train cars by this loader are
normally distributed, if a random sample of 9 loads is chosen for a weight check, find the probability that
the mean weight of those loads is more than 40.60 tons.
Place your answer, rounded to four decimal places, in the blank.
When entering your answer
do not use any labels or symbols other than a decimal point. Simply provide the numerical value. For
example, 0.1234 would be a legitimate entry.
Part 13 of 16 -
Question 20 of 23
1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces
(e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific
notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
Senior management of a consulting services firm is concerned about a growing decline in the firm’s
weekly number of billable hours. The firm expects each professional employee to spend at least 40 hours
per week on work. In an effort to understand this problem better, management would like to estimate the
standard deviation of the number of hours their employees spend on work-related activities in a typical
week. Rather than reviewing the records of all the firm’s full-time employees, the management randomly
selected a sample of size 51 from the available frame. The sample mean and sample standard
deviations were 48.5 and 7.5 hours, respectively.
Construct a 90% confidence interval for the standard deviation of the number of hours this firm’s
employees spend on work-related activities in a typical week.
Place your LOWER limit, in hours, rounded to 1 decimal place, in the first blank. For example, 6.7 would
be a legitimate entry.
Place your UPPER limit, in hours, rounded to 1 decimal place, in the second blank. For example, 12.3
would be a legitimate entry.
Part 14 of 16 -
Question 21 of 23
1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces
(e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific
notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
Suppose that the probability that a new medication will cause a bad side effect is
0.03. If this medication is given to 150 people, what is the probability that more than
three of them will experience a bad side effect? Place your answer, rounded to 4
decimal places, in the blank. For example, 0.1776 would be a legitimate answer.
Part 15 of 16 -
Question 22 of 23
1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces
(e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific
notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
A statistician wishes to test the claim that the standard deviation of the weights of firemen is greater than
25 pounds. To do so, she selected a random sample of 30 firemen and found s = 27.2 pounds.
Assuming that the weights of firemen are normally distributed, if the statistician wanted to test
her research hypothesis at the .05 level of significance, what is the critical value?
Place your answer, rounded to 3 decimal places, in the blank. For example, 23.456 would be a legitimate
entry.
Part 16 of 16 -
Question 23 of 23
1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces
(e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific
notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
A restaurant menu has a price-fixed complete dinner that consists of an appetizer,
entrée, beverage, and dessert. You have a choice of five appetizers, ten entrees, three
beverages, and six desserts. How many possible complete dinners are possible? Place
your answer, as a whole number—no decimal places—in the blank. For example 176
would be a legitimate entry