Question

I'm currently solving this, but I do not understand. If you can please show your work and formula. Thank you.

A random sample of 72 math majors generated the confidence interval (0.438, 0.642) to estimate the proportion of math majors that are female. What size sample would be necessary to estimate the true proportion within 2% using 98% reliability?

A. 3372

B. 3394

C. 3529

D. 3258

Answer #1

Solution :

Point estimate = = (Lower confidence interval + Upper confidence interval ) / 2

Point estimate = = (0.438 + 0.642) / 2

Point estimate = = 0.54

1 - = 1 - 0.54 = 0.46

margin of error = E = 0.02

At 98% confidence level

= 1 - 98%

= 1 - 0.98 =0.02

/2
= 0.01

Z/2
= Z0.01 = 2.33

sample size = n = (Z / 2 / E )2 * * (1 - )

= (2.33 / 0.02)2 * 0.54 * 0.46

= 3371.34

sample size = n = 3372

correct option is = A

A confidence interval was used to estimate the proportion of
statistics students who are female. A random sample of 72
statistics students generated the following confidence interval:
(.438, .642). Using the information above, what sample size would
be necessary if we wanted to estimate the true proportion to within
3% using 99% reliability?

I know this has been answered before but I do NOT understand.
Can you explain it better? We know n=900 and p-hat is .13, and 97.5
% confidence interval. An explanation would be appreciated for a
beginner.
According to a survey with 900 males, 13% are left-handed.
Construct a 97.5% confidence interval for the population
proportion of all males who are left-handed.
[3 marks]
If both the sample size and the number of successes are
doubled, what is the effect...

Please show work so I
can understand how to solve thanks
A random sample of 800
adults in Flagstaff found 24 adults who had lost a job in the past
year. Find a 95% confidence interval for the true percent of adults
in Flagstaff who have lost a job in the past year. Express
your results to the nearest hundredth of a percent. .
Answer: to %

1.)
You want to obtain a sample to estimate a population mean. Based
on previous evidence, you believe the population standard deviation
is σ=49.3σ=49.3. You would like to be 99% confident that you
estimate is within 5 of the true population mean.
How large of a sample size is required?
n =
Note: Use z-scores rounded to 3 decimal places in your
calculations.
2.)
You want to obtain a sample to estimate a population mean. Based
on previous evidence, you...

Could you please solve these using r code if necessary. If not
please show the work thank you.
2. Most penguin species are not sexually dimorphic, which means
they lack obvious outward body characteristics which indicate sex.
Observation of behavior or a blood test can determine Penguin sex.
A penguin researcher is interested in estimating the proportion of
females in a large penguin population. She takes a random sample of
n = 20 penguins and determines the sex of each...

sport illustrated asked a random sample of divison I colleges
athletes, "do you believe performance-enhancing drugs are a problem
in colleges?" 36% of the sample said "yes." if sports illustrated
wishes to estimate the true proportion concerned about drug use in
athletes within 2% with 98% confidence, how many people will they
have to interview?

If a hurricane was headed your way, would you evacuate? The
headline of a press release states, "Thirty-four Percent of People
on High-Risk Coast Will Refuse Evacuation Order, Survey of
Hurricane Preparedness Finds." This headline was based on a survey
of 6627 adults who live within 20 miles of the coast in high
hurricane risk counties of eight southern states. In selecting the
sample, care was taken to ensure that the sample would be
representative of the population of coastal...

Please show all work/steps so I can understand, also please
answer ASAP thank you!!!
Amy has started her own company, Amy Shirts, which makes Custom
Embroidered Logo polo shirts for special orders. Since she has just
begun this operation, she rents the equipment from a local shop
when necessary. The cost of using the equipment is $650. The
materials used in one shirt cost $12. Amy can sell these shirts for
$25 each.
(a) How many shirts must Amy sell...

I am having an issue with my school's math program but first
want to ensure it is the program and not my process.
Question-
You want to obtain a sample to estimate a population proportion.
At this point in time, you have no reasonable preliminary
estimation for the population proportion. You would like to be 99%
confident that you estimate is within 3.5% of the true population
proportion. How large of a sample size is required?
(1-0.99)/2 = 0.005 invNorm...

1) Find the sample size necessary to estimate the mean IQ score
of statistics students such that it can be said with 95%
confidence that the sample mean is ±7 IQ points of the true mean.
Assume that the standard deviation is
19 and determine the required sample size.
2) There are many reasons adults use credit cards. A recent
survey found that 47%
of adults used credit cards for convenience.
a. To conduct a follow-up study that would provide...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 1 minute ago

asked 17 minutes ago

asked 26 minutes ago

asked 30 minutes ago

asked 30 minutes ago

asked 32 minutes ago

asked 35 minutes ago

asked 38 minutes ago

asked 39 minutes ago

asked 59 minutes ago

asked 1 hour ago

asked 1 hour ago