Stats Test #3 Study Guide Quiz Questions with Complete
Solutions.
(Solve the problem)
Read the following problem description then choose the correct null and alternative
hypothesis. A 1) new drug is being tested to see whether it can reduce the rate of asthma
attacks in children ages 5 to
14. The rate of asthma attacks in the population of concern is 0.0744.
A) H0: p > 0.0744; Ha: p 0.0744
B) H0: p = 0.0744; Ha: p < 0.0744
C) H0: p = 0.0744; Ha: p > 0.0744
D) H0: p < 0.0744; Ha: p < 0.0744 - ✔✔✔ B) H0: p = 0.0744; Ha: p < 0.0744
(Solve Problem)
Read the following problem description then choose the correct null and alternative
hypothesis. A new drug is being tested to see whether it can reduce the rate of food-related
allergic reactions in children aged 1 to 3 with food allergies. The rate of allergic reactions in
the population of concern is
0.03.
A) H0: p = 0.03; Ha: p > 0.03
B) H0: p < 0.03; Ha: p = 0.03
C) H0: p = 0.03; Ha: p < 0.03
D) H0: p 0.03; Ha: p = 0.03 - ✔✔✔ C) H0: p = 0.03; Ha: p < 0.03
Which of the following is not true about the alternative hypothesis?
A) It is sometimes called the research hypothesis.
B) Like the null hypothesis, it is always a statement about a population parameter.
C) It is assumed to be true.
D) It is usually a statement that the researcher hopes to demonstrate is true. - ✔✔✔ C) It is
assumed to be true.
,Suppose that the following is to be tested: H0: p = 0.35 and Ha: p > 0.35. Calculate the
observed
z-statistic for the following sample data: Forty out of eighty test subjects have the
characteristic of interest. Round to the nearest hundredth.
A) z = -1.87
B) z = -0.94
C) z = 2.81
D) z = 1.88 - ✔✔✔ C) z = 2.81
Use the following information to answer the question. A janitor at a large office building
believes that his supply of light bulbs has a defect rate that is different than the defect rate
stated by the manufacturer. The janitor's null hypothesis is that the supply of light bulbs has
a defect rate of p = 0.09 (the light bulb manufacturer's stated defect rate). Suppose we do a
hypothesis test with a significance level of 0.01. Symbolically, the null and alternative
hypothesis are as follows: H0:
p = 0.09 and Ha: p > 0.09.
*Suppose the janitor tests 300 light bulbs and finds that 33 bulbs are defective. What value
of the test 5) statistic should he report? Round to the nearest hundredth.
A) z = -1.21
B) z = 2.17
C) z = -2.17
D) z = 1.21 - ✔✔✔ D) z = 1.21
A janitor at a large office building believes that his supply of light bulbs has a defect rate
that is higher than the defect rate stated by the manufacturer. The janitor's null hypothesis
is that the supply of light bulbs has a manufacturer's defect rate of p = 0.09. He performs a
test at a significance level of 0.01. The null and alternative hypothesis are as follows:
H0: p = 0.09 and Ha: p > 0.09.
*Suppose the janitor tests 300 light bulbs and finds that 33 bulbs are defective. The
calculated test 6) statistic is z = 1.21. Select the appropriate interpretation of the test
statistic.
A) A test statistic of 1.21 is 1.21 standard deviations less than the mean (between 1 and 2)
indicating that the result is not significant.
, B) A test statistic of 1.21 is 1.21 standard deviations greater than the mean (between 1 and
2) indicating that the result is not significant at a level of 0.01 using a one-sided alternative
hyp - ✔✔✔ B) A test statistic of 1.21 is 1.21 standard deviations greater than the mean
(between 1 and 2) indicating that the result is not significant at a level of 0.01 using a one-
sided alternative hypothesis.
Use the following information to answer the question. A janitor at a large office building
believes that his supply of light bulbs has too many defective bulbs. The janitor's null
hypothesis is that the supply of light bulbs has a defect rate of p = 0.07 (the light bulb
manufacturer's stated defect rate). Suppose he does a hypothesis test with a significance
level of 0.05. Symbolically, the null and alternative hypothesis are as follows: H0: p = 0.07
and Ha: p > 0.07.
*Choose the statement that best describes the significance level in the context of the
hypothesis test.
A) The significance level of 0.05 is the test statistic that we will use to compare the
observed
outcome to the null hypothesis.
B) The significance level of 0.05 is the probability of concluding that the defect rate is
higher than
0.07 when in fact the defect rate is equal to 0.07.
C) The significance level of 0.05 is the defect rate we believe i - ✔✔✔ B) The significance
level of 0.05 is the probability of concluding that the defect rate is higher than
0.07 when in fact the defect rate is equal to 0.07.
(Solve the Problem)
A polling agency is interested in testing whether the proportion of women who support a
female candidate for office is greater than the proportion of men. The null hypothesis is that
there is no difference in the proportion of men and women who support the female
candidate. The alternative hypothesis is that the proportion of women who support the
female candidate is greater than the proportion of men. The test results in a p-value of
0.112. Which of the following is the best interpretation of the p-value?
A) The p-value is the probability that men will support the female candidate.
B) The p-value is the probability of getting a result that is as extreme as or more extreme
than
the one obtained, assuming that the proportion of women who support the female
candidate
is greater than the proportion of men.
Solutions.
(Solve the problem)
Read the following problem description then choose the correct null and alternative
hypothesis. A 1) new drug is being tested to see whether it can reduce the rate of asthma
attacks in children ages 5 to
14. The rate of asthma attacks in the population of concern is 0.0744.
A) H0: p > 0.0744; Ha: p 0.0744
B) H0: p = 0.0744; Ha: p < 0.0744
C) H0: p = 0.0744; Ha: p > 0.0744
D) H0: p < 0.0744; Ha: p < 0.0744 - ✔✔✔ B) H0: p = 0.0744; Ha: p < 0.0744
(Solve Problem)
Read the following problem description then choose the correct null and alternative
hypothesis. A new drug is being tested to see whether it can reduce the rate of food-related
allergic reactions in children aged 1 to 3 with food allergies. The rate of allergic reactions in
the population of concern is
0.03.
A) H0: p = 0.03; Ha: p > 0.03
B) H0: p < 0.03; Ha: p = 0.03
C) H0: p = 0.03; Ha: p < 0.03
D) H0: p 0.03; Ha: p = 0.03 - ✔✔✔ C) H0: p = 0.03; Ha: p < 0.03
Which of the following is not true about the alternative hypothesis?
A) It is sometimes called the research hypothesis.
B) Like the null hypothesis, it is always a statement about a population parameter.
C) It is assumed to be true.
D) It is usually a statement that the researcher hopes to demonstrate is true. - ✔✔✔ C) It is
assumed to be true.
,Suppose that the following is to be tested: H0: p = 0.35 and Ha: p > 0.35. Calculate the
observed
z-statistic for the following sample data: Forty out of eighty test subjects have the
characteristic of interest. Round to the nearest hundredth.
A) z = -1.87
B) z = -0.94
C) z = 2.81
D) z = 1.88 - ✔✔✔ C) z = 2.81
Use the following information to answer the question. A janitor at a large office building
believes that his supply of light bulbs has a defect rate that is different than the defect rate
stated by the manufacturer. The janitor's null hypothesis is that the supply of light bulbs has
a defect rate of p = 0.09 (the light bulb manufacturer's stated defect rate). Suppose we do a
hypothesis test with a significance level of 0.01. Symbolically, the null and alternative
hypothesis are as follows: H0:
p = 0.09 and Ha: p > 0.09.
*Suppose the janitor tests 300 light bulbs and finds that 33 bulbs are defective. What value
of the test 5) statistic should he report? Round to the nearest hundredth.
A) z = -1.21
B) z = 2.17
C) z = -2.17
D) z = 1.21 - ✔✔✔ D) z = 1.21
A janitor at a large office building believes that his supply of light bulbs has a defect rate
that is higher than the defect rate stated by the manufacturer. The janitor's null hypothesis
is that the supply of light bulbs has a manufacturer's defect rate of p = 0.09. He performs a
test at a significance level of 0.01. The null and alternative hypothesis are as follows:
H0: p = 0.09 and Ha: p > 0.09.
*Suppose the janitor tests 300 light bulbs and finds that 33 bulbs are defective. The
calculated test 6) statistic is z = 1.21. Select the appropriate interpretation of the test
statistic.
A) A test statistic of 1.21 is 1.21 standard deviations less than the mean (between 1 and 2)
indicating that the result is not significant.
, B) A test statistic of 1.21 is 1.21 standard deviations greater than the mean (between 1 and
2) indicating that the result is not significant at a level of 0.01 using a one-sided alternative
hyp - ✔✔✔ B) A test statistic of 1.21 is 1.21 standard deviations greater than the mean
(between 1 and 2) indicating that the result is not significant at a level of 0.01 using a one-
sided alternative hypothesis.
Use the following information to answer the question. A janitor at a large office building
believes that his supply of light bulbs has too many defective bulbs. The janitor's null
hypothesis is that the supply of light bulbs has a defect rate of p = 0.07 (the light bulb
manufacturer's stated defect rate). Suppose he does a hypothesis test with a significance
level of 0.05. Symbolically, the null and alternative hypothesis are as follows: H0: p = 0.07
and Ha: p > 0.07.
*Choose the statement that best describes the significance level in the context of the
hypothesis test.
A) The significance level of 0.05 is the test statistic that we will use to compare the
observed
outcome to the null hypothesis.
B) The significance level of 0.05 is the probability of concluding that the defect rate is
higher than
0.07 when in fact the defect rate is equal to 0.07.
C) The significance level of 0.05 is the defect rate we believe i - ✔✔✔ B) The significance
level of 0.05 is the probability of concluding that the defect rate is higher than
0.07 when in fact the defect rate is equal to 0.07.
(Solve the Problem)
A polling agency is interested in testing whether the proportion of women who support a
female candidate for office is greater than the proportion of men. The null hypothesis is that
there is no difference in the proportion of men and women who support the female
candidate. The alternative hypothesis is that the proportion of women who support the
female candidate is greater than the proportion of men. The test results in a p-value of
0.112. Which of the following is the best interpretation of the p-value?
A) The p-value is the probability that men will support the female candidate.
B) The p-value is the probability of getting a result that is as extreme as or more extreme
than
the one obtained, assuming that the proportion of women who support the female
candidate
is greater than the proportion of men.
