Question 1 of 20
1.0 Points
The hypothesis that an analyst is trying to prove is called the:
A.alternative hypothesis
B.quality of the researcher
C.level of significance
D.elective hypothesis
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Question 2 of 20
1.0 Points
If a teacher is trying to prove that a new method of teaching economics is more effective than a traditional
one, he/she will conduct a:
A.two-tailed test
B.point estimate of the population parameter
C.one-tailed test
D.confidence interval
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Question 3 of 20
1.0 Points
A null hypothesis can only be rejected at the 5% significance level if and only if:
A.a 95% confidence interval does not include the hypothesized value of the parameter
B.the null hypothesis is biased
C.a 95% confidence interval includes the hypothesized value of the parameter
D.the null hypotheses includes sampling error
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Question 4 of 20
1.0 Points
In an article appearing in Todays 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.
Compute the z or t value of the sample test statistic.
A.t = 1.916
B.t = -1.916
C.z = 1.916
D.z = 1.645
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Question 5 of 20
1.0 Points
Which of the following statements are true of the null and alternative hypotheses?
A.It is possible for neither hypothesis to be true
B.Both hypotheses must be true
C.Exactly one hypothesis must be true
D.It is possible for both hypotheses to be true
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Question 6 of 20
1.0 Points
The Pizza Hot manager commits a Type I error if he/she is
A.switching to new style when it is better than old style
B.staying with old style when new style is no better than old style
C.staying with old style when new style is better
D.switching to new style when it is no better than old style
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Question 7 of 20
1.0 Points
You conduct a hypothesis test and you observe values for the sample mean and sample standard
deviation when n = 25 that do not lead to the rejection of H 0. You calculate a p-value of 0.0667. What will
happen to the p-value if you observe the same sample mean and standard deviation for a sample size
larger than 25?
A.The p value increases
B.The p value may increase or decrease
C.The p value stays the same
D.The p value decreases
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Question 8 of 20
1.0 Points
In an article appearing in Todays 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.
At the = .05 level of significance, does the nutritionist have enough evidence to reject the
writers claim?
A.No
B.Yes
C.Cannot Determine
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Question 9 of 20
1.0 Points
Results from previous studies showed 79% of all high school seniors from a certain city
plan to attend college after graduation. A random sample of 200 high school seniors
from this city reveals that 162 plan to attend college. Does this indicate that the
percentage has increased from that of previous studies? Test at the 5% level of
significance.
What is your conclusion?
A.More seniors are going to college
B.Reject H0. There is enough evidence to support the claim that the proportion of students planning to
go to college is now greater than .79.
C.Cannot determine
D.Do not reject H0. There is not enough evidence to support the claim that the proportion of students
planning to go to college is greater than .79.
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Question 10 of 20
The null and alternative hypotheses divide all possibilities into:
A.as many sets as necessary to cover all possibilities
B.two non-overlapping sets
C.two sets that overlap
1.0 Points
D.two sets that may or may not overlap
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Question 11 of 20
1.0 Points
Results from previous studies showed 79% of all high school seniors from a certain city plan to attend
college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan
to attend college. Does this indicate that the percentage has increased from that of previous studies? Test
at the 5% level of significance.
State the null and alternative hypotheses.
A.H0:
= .79, H1: > .79
B.H0: p .79, H1: p > .79
C.
:
= .79, H1:
D.H0: p
> .79
= .79, H1: p .79
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Part 2 of 3 –
Question 12 of 20
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.
The ABC battery company claims that their batteries last at least 100 hours, on average. Your experience
with their batteries has been somewhat different, so you decide to conduct a test to see if the company’s
claim is true. You believe that the mean life is actually less than the 100 hours the company claims. You
decide to collect data on the average battery life (in hours) of a random sample of n = 20 batteries. Some
of the information related to the hypothesis test is presented below.
Test of H0:
100 versus H1:
100
Sample mean 98.5
Std error of mean 0.777
Assuming the life length of batteries is normally distributed, if you wish to conduct this test using a .05
level of significance, what is the critical value that you should use? Place your answer, rounded to 3
decimal places in the blank. For example, -1.234 would be a legitimate entry.
Question 13 of 20
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 medical doctor wishes to test the claim that the standard deviation of the systolic blood pressure of deep
sea divers is less than 450. To do so, she selected a random sample of 20 divers and found s = 432.
Assuming that the systolic blood pressures of deep sea divers are normally distributed, if the doctor
wanted to test her research hypothesis at the .01 level of significance, what is the critical value?
Place your answer, rounded to 3 decimal places, in the blank. For example, 4.567 would be a legitimate
entry.
Question 14 of 20
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 a firm that produces light bulbs wants to know whether it can say that its light bulbs typically last
more than 1500 hours. Hoping to find support for their claim, the firm collects a random sample of n = 25
light bulbs and records the lifetime (in hours) of each bulb. The information related to the hypothesis test is
presented below.
Test of H0:
1500 versus H1:
> 1500
Sample mean 1509.5
Std error of mean 4.854
Assuming the life length of this type of lightbulb is normally distributed, if you wish to conduct this test
using a .05 level of significance, what is the critical value that you should use? Place your answer,
rounded to 3 decimal places in the blank. For example, 1.234 would be a legitimate entry.
Question 15 of 20
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 20 firemen and found s = 27.2 pounds.
Assuming that the weights of firemen are normally distributed, to test her research hypothesis the
statistician would use a chi-square test. In that case, what is the computed test value?
Place your answer, rounded to 3 decimal places, in the blank. For example, 23.456 would be a legitimate
entry.
Question 16 of 20
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.
The ABC battery company claims that their batteries last 100 hours, on average. You decide to conduct a
test to see if the company’s claim is true. You believe that the mean life may be different from the 100
hours the company claims. You decide to collect data on the average battery life (in hours) of a random
sample of n = 20 batteries. Some of the information related to the hypothesis test is presented below.
Test of H0:
= 100 versus H1:
100
Sample mean 98.5
Std error of mean 0.777
Assuming the life length of batteries is normally distributed, what is the p-value associated with this test?
Place your answer, rounded to 3 decimal places in the blank. For example, 0.234 would be a legitimate
entry.
1.0 Points
Question 17 of 20
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 firm that produces light bulbs claims that their lightbulbs last 1500 hours, on average. You wonder if the
average might differ from the 1500 hours that the firm claims. To explore this possibility you take a
random sample of n = 25 light bulbs purchased from this firm and record the lifetime (in hours) of each
bulb. You then conduct an appopriate test of hypothesis. Some of the information related to the
hypothesis test is presented below.
Test of H0:
= 1500 versus H1:
1500
Sample mean 1509.5
Std error of mean 4.854
Assuming the life length of this type of lightbulb is normally distributed, if you wish to conduct this test
using a .05 level of significance, what are the critical values that you should use? Place the smallest
critical value, rounded to 3 decimal places, in the first blank. For example, -1.234 would be a legitimate
entry.
. Place the larger critical value, rounded to 3 decimal places, in the second blank. For
example, 1.234 would be a legitimate entry.
Part 3 of 3 –
Question 18 of 20
1.0 Points
The p-value of a test is the smallest level of significance at which the null hypothesis can be rejected.
True
False
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Question 19 of 20
1.0 Points
The probability of making a Type I error and the level of significance are the same.
True
False
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Question 20 of 20
A one-tailed alternative is one that is supported by evidence in either direction.
True
False
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1.0 Points
