Deck 8: Hypothesis Testing

Question 1

Answer 1

C

Question 2

Answer 2

A

Question 3

Answer 3

C

Question 4

Question 5

Question 6

A Type I error is the mistake of ________________ when it is actually true. 17)__________

A) failing to reject the null hypothesis
B) failing to reject the alternative hypothesis
C) rejecting the null hypothesis
D) rejecting the alternative hypothesis

Question 7

Suppose we want to test the claim that the majority of adults are in favor of raising the voting 20)__________ age to 21. Is the hypothesis test left-tailed, right-tailed, or two-tailed?

A) Left-tailed
B) Right-tailed
C) Two-tailed

Question 8

Question 9

Question 10

Question 11

Formulate the indicated conclusion in nontechnical terms. Be sure to address the original claim. The principal of a middle school claims that test scores of the seventh-graders at his school
Vary less than the test scores of the seventh-graders at a neighboring school, which have
Variation described by . Assuming that a hypothesis test of the claim has been
Conducted and that the conclusion is to reject the null hypothesis, state the conclusion in
Nontechnical terms.

A) There is sufficient evidence to support the claim that the standard deviation is greater than 14.7.
B) There is sufficient evidence to support the claim that the standard deviation is less than 14.7.
C) There is not sufficient evidence to support the claim that the standard deviation is greater than 14.7.
D) There is not sufficient evidence to support the claim that the standard deviation is less than 14.7.

Question 12

Question 13

Formulate the indicated conclusion in nontechnical terms. Be sure to address the original 11)__________ claim. Carter Motor Company claims that its new sedan, the Libra, will average better than 32
Miles per gallon in the city. Assuming that a hypothesis test of the claim has been conducted
And that the conclusion is to reject the null hypothesis, state the conclusion in nontechnical
Terms.

A) There is sufficient evidence to support the claim that the mean is greater than 32 miles per gallon.
B) There is not sufficient evidence to support the claim that the mean is greater than 32 miles per gallon.
C) There is not sufficient evidence to support the claim that the mean is less than 32 miles per gallon.
D) There is sufficient evidence to support the claim that the mean is less than 32 miles per gallon.

Question 14

Use the given information to find the P-value. Also, use a 0.05 significance level and state the 7)__________ conclusion about the null hypothesis (reject the null hypothesis or fail to reject the null
Hypothesis). The test statistic in a right-tailed test is z = 0.52.

A) 0.6030; fail to reject the null hypothesis
B) 0.3015; reject the null hypothesis
C) 0.0195; reject the null hypothesis
D) 0.3015; fail to reject the null hypothesis

Question 15

Express the original claim in symbolic form. 14)__________ Claim: 20% of adults smoke

Question 16

The ________________ is the probability of getting a test statistic at least as extreme as the 18)__________ one representing the sample data, assuming that the null hypothesis is true.

A) P-value
B) sample proportion
C) critical value
D) level of significance

Question 17

Find the P-value in a test of the claim that the mean IQ score of acupuncturists is equal to 100, 15)__________ given that the test statistic is z =−2.00.

A) 0.0228
B) 0.955
C) 0.977
D) 0.0455

Question 18

A hypothesis test is performed to test the claim that a population proportion is greater than 0.7. 5)__________ Find the probability of a type II error, , given that the true value of the population proportion
Is 0.72. The sample size is 50 and the significance level is 0.05.

A) 0.4129
B) 0.5754
C) 0.7123
D) 0.9706

Question 19

Question 20

Question 21

Question 22

Find the P-value for the indicated hypothesis test. An article in a journal reports that 34% of American fathers take no responsibility for child care. A researcher claims that the figure is
Higher for fathers in the town of Littleton. A random sample of 225 fathers from Littleton,
Yielded 97 who did not help with child care. Find the P -value for a test of the researcher's
Claim.

A) 0.0015
B) 0.0038
C) 0.0529
D) 0.0019

Question 23

Formulate the indicated conclusion in nontechnical terms. Be sure to address the original claim. Carter Motor Company claims that its new sedan, the Libra, will average better than 32 miles
Per gallon in the city. Assuming that a hypothesis test of the claim has been conducted and
That the conclusion is to reject the null hypothesis, state the conclusion in nontechnical terms.

A) There is not sufficient evidence to support the claim that the mean is greater than 32 miles per gallon.
B) There is not sufficient evidence to support the claim that the mean is less than 32 miles per gallon.
C) There is sufficient evidence to support the claim that the mean is less than 32 miles per gallon.
D) There is sufficient evidence to support the claim that the mean is greater than 32 miles per gallon.

Question 24

Question 25

.

Question 26

Formulate the indicated conclusion in nontechnical terms. Be sure to address the original claim. The owner of a football team claims that the average attendance at games is over 523, and he is
Therefore justified in moving the team to a city with a larger stadium. Assuming that a
Hypothesis test of the claim has been conducted and that the conclusion is failure to reject the
Null hypothesis, state the conclusion in nontechnical terms.

A) There is sufficient evidence to support the claim that the mean attendance is less than 523.
B) There is not sufficient evidence to support the claim that the mean attendance is less than 523.
C) There is sufficient evidence to support the claim that the mean attendance is greater than 523.
D) There is not sufficient evidence to support the claim that the mean attendance is greater than 523.

Question 27

Question 28

Question 29

Assume that a hypothesis test of the given claim will be conducted. Identify the type I or type II error for the test. A consumer advocacy group claims that the mean mileage for the Carter
Motor Company's new sedan is less than 32 miles per gallon. Identify the type I error for the
Test.

A) Reject the claim that the mean is equal to 32 miles per gallon when it is actually less than 32 miles per gallon.
B) Fail to reject the claim that the mean is equal to 32 miles per gallon when it is actually less than 32 miles per gallon.
C) Fail to reject the claim that the mean is equal to 32 miles per gallon when it is actually greater than 32 miles per gallon.
D) Reject the claim that the mean is equal to 32 miles per gallon when it is actually 32 miles per gallon.

Question 30

Question 31

Suppose we want to test the claim that less than of Americans are in favor of raising the voting age to 21. Is the hypothesis test left-tailed, right-tailed, or two-tailed?

A) Left-tailed
B) Right-tailed
C) Two-tailed
114

Question 32

Question 33

A _____________ error is the mistake of rejecting the null hypothesis when it is actually true.

A) Type I
B) Type II
C) Type III
D) Type IV

Question 34

Find the P-value in a test of the claim that the mean College Algebra final exam score of engineering majors equal to 88, given that the test statistic is z = 1.50.

A) 0.0668
B) 0.9331
C) 0.1336
D) 0.1500

Question 35

Question 36

Question 37

The p-value is the probability of getting a test statistic at least as extreme as the one representing the sample data, assuming that ______________________________.

A) the null hypothesis is true
B) the null hypothesis is false
C) the alternative hypothesis is true
D) the alternative hypothesis is false

Question 38

Question 39

Solve the problem. A hypothesis test is performed to test the claim that a population proportion is greater than 0.7. Find the probability of a type II error, , given that the true value of the
Population proportion is 0.72. The sample size is 50 and the significance level is 0.05.

A) 0.4129
B) 0.7123
C) 0.5754
D) 0.9706

Question 40

Question 41

An oil change shop claims that they will change your oil in under 15 minutes. To test this
claim, a consumer advocacy group takes a simple random sample of 10 customers and records
the number of minutes it took to complete oil changes for these customers. Assume that oil
change times are normally distributed. Conduct a hypothesis test for the oil shop's claim about oil change times at the 5% level of
significance.
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Question 42

Assume that a simple random sample has been selected from a normally distributed population
and test the given claim. Use either the traditional method or P-value method as indicated.
Identify the null and alternative hypotheses, test statistic, critical value(s)or P-value (or range
of P-values)as appropriate, and state the final conclusion that addresses the original claim.
A cereal company claims that the mean weight of the cereal in its packets is 14 oz. The
weights (in ounces)of the cereal in a random sample of 8 of its cereal packets are listed below. Test the claim at the 0.01 significance level.

Question 43

Question 44

Question 45

Solve the problem. What do you conclude about the claim below? Do not use formal
procedures or exact calculations. Use only the rare event rule and make a subjective estimate to
determine whether the event is likely.
Claim: A roulette wheel is fair and in 40 consecutive spins of the wheel, black shows up 23
times. (A roulette wheel has 38 equally likely slots of which 18 are black).

Question 46

Question 47

Question 48

Solve the problem. Use the P-value method to test the claim that the population standard
deviation of the systolic blood pressures of adults aged 40-50 is equal to 22 mmHg. The
sample statistics are as follows: nx==23, 132.2 mmHg, s = 26.6 mmHg. Be sure to state
the hypotheses, the value of this test statistic, the P-value, and your conclusion. Use a
significance level of 0.05.

Question 49

What do you conclude about the claim below? Do not use formal procedures or exact
calculations. Use only the rare event rule and make a subjective estimate to determine whether
the event is likely.
Claim: A die is fair and in 100 rolls there are 63 sixes.

Question 50

Test the given claim. Use the P-value method or the traditional method as indicated.
the null hypothesis, alternative hypothesis, test statistic, critical value(s)or P-value,
conclusion about the null hypothesis, and final conclusion that addresses the original claim.
The mean resting pulse rate for men is 72 beats per minute. A simple random sample of
men who regularly work out at Mitch's Gym is obtained and their resting pulse rates (in beats
per minute)are listed below. Use a 0.05 significance level to test the claim that these sample
pulse rates come from a population with a mean less than 72 beats per minute. Assume that
the standard deviation of the resting pulse rates of all men who work out at Mitch's Gym is
known to be 6.6 beats per minute. Use the traditional method of testing hypotheses.

Question 51

Identify the null hypothesis, alternative hypothesis, test statistic, P -value, conclusion about
the null hypothesis, and final conclusion that addresses the original claim. An article in a
journal reports that 34% of American fathers take no responsibility for child care. A
researcher claims that the figure is higher for fathers in the town of Littleton. A random
sample of 234 fathers from Littleton yielded 96 who did not help with child care. Test the
researcher's claim at the 0.05 significance level.

Question 52

A simple random sample of the running time of movies of 70 international movies resulted in
a sample mean length of 112 minutes and a sample standard deviation of 7 minutes. Test the
claim that international movies have a mean running time of more than 110 minutes at the 5%
level of significance. Assume that the lengths of movies are normally distributed.

Question 53

Question 54

Use the traditional method to test the given hypothesis. Assume that the population is normally
distributed and that the sample has been randomly selected. For randomly selected adults, IQ
scores are normally distributed with a standard deviation of 15. The scores of 14 randomly
selected college students are listed below. Use a 0.10 significance level to test the claim that
the standard deviation of IQ scores of college students is less than 15. Round the sample
standard deviation to three decimal places.

Question 55

Sam wanted to test a claim about the mean of a population whose standard deviation was
unknown. He picked a simple random sample of size 20 from the population. Lou wanted to
test a claim about a mean of a different population whose standard deviation was known. He
picked a simple random sample of size 22 from that population. George said that Sam would
need to determine whether his sample was from a normally distributed population because the
population standard deviation was unknown. He said that Lou would not need to do this since
for his test the population standard deviation was known. Is George right?
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Question 56

Assume that a simple random sample has been selected from a normally distributed population
and test the given claim. Use either the traditional method or P-value method as indicated.
Identify the null and alternative hypotheses, test statistic, critical value(s)or P-value (or range
of P-values)as appropriate, and state the final conclusion that addresses the original claim. A
light-bulb manufacturer advertises that the average life for its light bulbs is 900 hours.
A random sample of 15 of its light bulbs resulted in the following lives in hours. At the 10% significance level, test the claim that the sample is from a population with a
mean life of 900 hours. Use the P-value method of testing hypotheses.

Question 57

Use the traditional method to test the given hypothesis. Assume that the population is normally
distributed and that the sample has been randomly selected. A manufacturer uses a new
production method to produce steel rods. A random sample of 17 steel rods resulted in lengths
with a standard deviation of 4.7 cm. At the 0.10 significance level, test the claim that the new
production method has lengths with a standard deviation different from 3.5 cm, which was the
standard deviation for the old method.

Question 58

Use the traditional method to test the given hypothesis. Assume that the population is normally
distributed and that the sample has been randomly selected. Heights of men aged 25 to 34
have a standard deviation of 2.9. Use a 0.05 significance level to test the claim that the heights
of women aged 25 to 34 have a different standard deviation. The heights (in inches)of 16
randomly selected women aged 25 to 34 are listed below. Round the sample standard
deviation to five decimal places.

Question 59

Solve the problem. Suppose that you are conducting a study on the effectiveness of a new
teaching method and that you wish to use a hypothesis test to support your claim regarding
the mean test score under this method. What restrictions are there in the wording of the claim?
Will your claim become the null hypothesis or the alternative hypothesis, or does it depend on
the situation? Give an example of a claim which is incorrectly worded.

Question 60

Assume that a simple random sample has been selected from a normally distributed population
and test the given claim. Use either the traditional method or P-value method as indicated.
Identify the null and alternative hypotheses, test statistic, critical value(s)or P-value (or range
of P-values)as appropriate, and state the final conclusion that addresses the original claim. A
public bus company official claims that the mean waiting time for bus number 14 during peak
hours is less than 10 minutes. Karen took bus number 14 during peak hours on 18 different
occasions. Her mean waiting time was 7.6 minutes with a standard deviation of 2.3 minutes.
At the 0.01 significance level, test the claim that the mean waiting time is less than 10
minutes. Use the P-value method of testing hypotheses.