Question

A certain region would like to estimate the proportion of voters who intend to participate in upcoming elections. A pilot sample of 25 voters found that 21 of them intended to vote in the election. Determine the additional number of voters that need to be sampled to construct a 98?% interval with a margin of error equal to 0.04 to estimate the proportion.

Answer #1

Solution :

Given that,

n = 25

x = 21

= x / n = 21 / 25 = 0.84

1 - = 1 - 0.84 = 0.16

Margin of error = E = 0.04

At 98% confidence level the z is ,

= 1 - 98% = 1 - 0.98 = 0.02

/ 2 = 0.02 / 2 = 0.01

Z_{/2} =
Z_{0.01} = 2.326

Sample size = ( Z_{/2} /
E)^{2} * * (1 - )

= (2.326 / 0.04)^{2} * 0.5 * 0.5

= 454.46 = 455

The additional number of voters that need to be sampled is = 455

A certain region would like to estimate the proportion of voters
who intend to participate in upcoming elections. A pilot sample of
25 voters found that 17 of them intended to vote in the election.
Determine the additional number of voters that need to be sampled
to construct a 96?% interval with a margin of error equal to 0.05
to estimate the proportion.

Suppose a hospital would like to estimate the proportion of
patients who feel that physicians who care for them always
communicated effectively when discussing their medical care. A
pilot sample of 40 patients found that 18 reported that their
physician communicated effectively. Determine the additional number
of patients that need to be sampled to construct a 95% confidence
interval with a margin of error equal to 3% to estimate this
proportion.

A survey of 250 voters was conducted to determine who they would
vote for in an upcoming election for sheriff. Fifty-five percent
said they would vote for Longmire.
A/ What is the best unbiased estimate of the population
proportion that will vote for Longmire (in other words, what is
?)
B/ Find the margin of error E that corresponds to a 90% confidence
Interval.
C/ Construct the 90% confidence interval about the population
proportion p.
D/ Based on your results,...

Before elections polling companies survey voters. They want to
estimate the proportion of voters who plan to vote for each
candidate . As the election gets closer polling companies often use
larger sample sizes in their surveys. Why they do this? Alarger
size gives more voters the opportunity to give their opinion A
sample site help fix poor sampling methods. With a larger sample
size the polling company can be certain that their sample results
exactly match the population Alarger...

You wish to estimate the proportion of registered voters who
plan to vote for Candidate Cal Q. Later in the upcoming election.
To do this, you will take a random sample of all registered voters.
A poll last month showed Cal with 70% of the votes. How big a
sample do you need for a margin of error of four percentage points
and a confidence level of 90%?

6) A newspaper polls 58 voters to ask which candidate for mayor
the supported in an upcoming election.
Of the 58 people polled, 20 said that they intended to vote for
Candidate Jones.
a) Find a 99% confidence interval for the true proportion of
people in the city who plan to vote for Candidate Jones.
b) Provide the margin of error of the interval as your
answer.
Round your answer to 4 decimal places.

The U.S. Department of Transportation would like to estimate the
proportion of drivers that are uninsured in the state of
Mississippi. A pilot sample of 60 drivers from Mississippi found
that 18 were uninsured. Determine the total sample size needed to
construct a 99% confidence interval for the proportion of uninsured
drivers in Mississippi with a margin of error equal to 5%.
Use the z-score with three decimal places, Remember the rounding
policy for sample size

In a recent poll, 134 registered voters who planned to
vote in the next election were asked if they would vote for a
particular candidate and 80 of these people responded that they
would. We wish to predict the proportion of people who will vote
for this candidate in the election.
a) Find a point estimator of the proportion who would vote for
this candidate.
b) Construct a 90% confidence interval for the true proportion
who would vote for this...

In a recent poll, 134 registered voters who planned to vote in
the next election were asked if they would vote for a particular
candidate and 80 of these people responded that they would. 1. 1.
We wish to predict the proportion of people who will vote for this
candidate in the election.
a) Find a point estimator of the proportion who would vote for
this candidate.
b) Construct a 90% confidence interval for the true proportion
who would vote...

You are working for a certain candidate who is running a
provincial election. This candidate finds out that you have taken a
statistics course from a certain statistics professor, and assumes
that you know a bit about statistics and sampling. The candidate
asks you to take a poll in order to estimate the proportion of the
voters who cast their vote for him/her with a margin of error of
0.035. You take it upon yourself to take a simple random...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 5 minutes ago

asked 5 minutes ago

asked 16 minutes ago

asked 17 minutes ago

asked 29 minutes ago

asked 29 minutes ago

asked 32 minutes ago

asked 53 minutes ago

asked 55 minutes ago

asked 58 minutes ago

asked 1 hour ago

asked 1 hour ago