Question

A poll done for an organization found that 13% of Americans have
seen or sensed the presence of an angel. A contingent doubts that
the percent is really that high. It conducts its own survey. Out of
78 Americans surveyed, only two had seen or sensed the presence of
an angel. As a result of the contingent's survey, would you agree
with the organization's poll? Conduct a hypothesis test at the 5%
level.

Note: If you are using a Student's *t*-distribution for the
problem, you may assume that the underlying population is normally
distributed. (In general, you must first prove that assumption,
though.)

1. State the distribution to use for the test. (Enter your
answer in the form *z* or *t*_{df}
where *df* is the degrees of freedom.)

2. What is the test statistic? (If using the *z*
distribution round your answers to two decimal places, and if using
the *t* distribution round your answers to three decimal
places.)

3. What is the *p*-value? (Round your answer to four
decimal places.)

4. Construct a 95% confidence interval for the true proportion. Sketch the graph of the situation. Label the point estimate and the lower and upper bounds of the confidence interval. (Keep in mind that a negative value wouldn't be practical in this situation. Round your answers to four decimal places.)

5. Give three reasons why the two polls might give different results. (Select all that apply.)

A. The polls may have been worded differently.

B. One of the polls may have included more people wearing glasses.

C. One of the polls may have been conducted later in the day.

D. One of the polls may have included more people who consider themselves religious.

E. Random chance could account for some of the difference.

Answer #1

A researching team conduct a survey, where out of 76 Americans
surveyed, only 2 had seen or sensed the presence of an angel. Test
the claim that 13% of Americans have seen or sensed the presence of
an angel. Use α = 0.05

Using TI 83 Calculator Only
Show All Steps
1. The average work week for engineers in a start-up company
is believed to be about 60 hours. A newly hired engineer hopes that
it’s shorter. She asks 10 engineering friends in start-ups for the
lengths of their average work weeks. Based on the results that
follow, should she count on the
average work week to be shorter than 60 hours?
Data (length of average work week): 70; 45; 55; 60; 65;...

Employee Satisfaction Rates: A recent poll suggests that 48% of
Americans are satisfied with their job. You have a company with 226
employees and a poll suggests that 89 of them are satisfied (about
39%). (a) Assume the 48% general satisfaction rate is accurate. In
all random samples of 226 Americans, what is the mean and standard
deviation for the number of people satisfied with their job? Round
both answers to 1 decimal place. \muμ = \sigmaσ = (b) Convert...

A telephone poll of 1000 adult Americans was reported in a
magazine. One of the questions asked was "What is the main problem
facing the country?" Suppose 18% answered "crime". We are
interested in the population proportion of adult Americans who feel
that crime is the main problem.
NOTE: If you are using a Student's t-distribution, you may
assume that the underlying population is normally distributed. (In
general, you must first prove that assumption, though.)
Construct a 95% confidence interval...

The mean number of sick days an employee takes per year is
believed to be about 10. Members of a personnel department do not
believe this figure. They randomly survey 8 employees. The number
of sick days they took for the past year are as follows: 10; 5; 15;
5; 9; 10; 6; 9. Let X = the number of sick days they took
for the past year. Should the personnel team believe that the mean
number is about 10?...

A telephone poll of 1000 adult Americans was reported in an
issue of a magazine. One of the questions asked was "[How much are]
you worried about the quality of education in our schools?" Suppose
64% responded "a lot". We are interested in the population
proportion of adult Americans who are worried a lot about the
quality of education in our schools.
Which distribution should you use for this problem? (Round your
answers to three decimal places.)
P' ~ N...

An article in the San Jose Mercury News stated that
students in the California state university system take 4.5 years,
on average, to finish their undergraduate degrees. Suppose you
believe that the mean time is longer. You conduct a survey of 43
students and obtain a sample mean of 5.1 with a sample standard
deviation of 1.2. Do the data support your claim at the 1%
level?
Note: If you are using a Student's t-distribution for the
problem, you may...

A Gallup poll conducted in November 2010 found that 493 of 1050
adult Americans believe it is the responsibility of the federal
government to make sure all Americans have healthcare coverage.
Use Minitab Express to construct the following confidence
intervals. Report your answers as decimals (not
percents) rounded to three decimal places, where applicable.
a) We are 95% confident that
the proportion of all adult Americans who believe it is the
responsibility of the federal government to make sure all Americans...

A Gallup poll to survey the top concerns of Americans was
conducted. Suppose that 713 women and 613 men were independently
and randomly selected, and that 338 women and 244 men chose the
state of the economy as their biggest concern. Can we conclude that
the proportion of women ( p1 ), choosing the state of the economy
as their biggest concern, exceeds the proportion of men ( p2
)? Use a significance level of α=0.1 for the test.
Step 1...

A Gallup poll to survey the top concerns of Americans was
conducted. Suppose that 366366 women and 422422 men were
independently and randomly selected, and that 202202 women and
186186 men chose the state of the economy as their biggest concern.
Can we conclude that the proportion of women ( p1p1 ), choosing the
state of the economy as their biggest concern, exceeds the
proportion of men ( p2p2 )? Use a significance level of
α=0.05α=0.05 for the test.
Step 1...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 10 minutes ago

asked 38 minutes ago

asked 43 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago