Question

A researcher wants to estimate, with 90% confidence, the proportion of people who use Instagram as their main social media. A previous study showed that 42% of those interviewed had a computer at their home. The researcher wishes to be accurate within 3% of the true proportion. How many people must the researcher survey? Show formula, substuon, a

Answer #1

Solution :

Given that,

= 0.42

1 - = 1 - 0.42 = 0.58

margin of error = E = 3% = 0.03

At 90% confidence level

= 1 - 90%

= 1 - 0.90 =0.10

/2
= 0.05

Z/2
= Z0.05 = 1.645 ( Using z table )

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

= (1.645 / 0.03)2 * 0.42 * 0.58

=732.43

Sample size = 733

A music industry researcher wants to estimate, with a 95%
confidence level, the proportion of young urban people (ages 21 to
35 years) who go to at least 3 concerts a year. Previous studies
show that 42% of those people (21 to 35 year olds) interviewed go
to at least 3 concerts a year. The researcher wants to be accurate
within 1% of the true proportion. Find the minimum sample size
necessary.
Choose one:
a) 9604
b) 9385
c) 9358...

A researcher wishes to estimate, with 90% confidence, the
population proportion of adults who think Congress is doing a good
or excellent job. Her estimate must be accurate within 33% of the
true proportion.
(a) No preliminary estimate is available. Find the minimum
sample size needed.
(b) Find the minimum sample size needed, using a prior study
that found that 42%
of the respondents said they think Congress is doing a good or
excellent job.
(c) Compare the results from...

A researcher wishes to estimate, with 90% confidence, the
population proportion of adults who think Congress is doing a good
or excellent job. Her estimate must be accurate within 1% of the
true proportion. (a) No preliminary estimate is available. Find
the minimum sample size needed. (b) Find the minimum sample size
needed, using a prior study that found that 40% of the respondents
said they think Congress is doing a good or excellent job. (c)
Compare the results from...

A researcher wishes to? estimate, with 90?% ?confidence, the
population proportion of adults who say chocolate is their favorite
ice cream flavor. Her estimate must be accurate within 5?% of the
population proportion. ?(a) No preliminary estimate is available.
Find the minimum sample size needed. ?(b) Find the minimum sample
size? needed, using a prior study that found that 36?% of the
respondents said their favorite flavor of ice cream is chocolate.
?(c) Compare the results from parts? (a) and?...

A researcher wishes to estimate, with 90% confidence, the
population proportion of adults who think Congress is doing a good
or excellent job. Her estimate must be accurate within 22% of the
true proportion.
(a) No preliminary estimate is available. Find the minimum
sample size needed.
(b) Find the minimum sample size needed, using a prior study
that found that 26% of the respondents said they think Congress is
doing a good or excellent job.
(c) Compare the results from...

A researcher wishes to estimate, with 90% confidence, the
population proportion of adults who eat fast food four to six times
per week. Her estimate must be accurate within 5% of the
population proportion. (a) No preliminary estimate is available.
Find the minimum sample size needed. (b) Find the minimum sample
size needed, using a prior study that found that 38% of the
respondents said they eat fast food four to six times per week.
(c) Compare the results from...

A researcher wishes to estimate, with 90% confidence, the
population proportion of adults who think the president of their
country can control the price of gasoline. Her estimate must be
accurate within 4% of the true proportion. No preliminary estimate
is available. Find the minimum sample size needed. Find the minimum
sample size needed, using a prior study that found that 28% of the
respondents said they think their president can control the price
of gasoline. Compare the results. What...

A researcher wishes to estimate, with 99% confidence, the
population proportion of adults who think the president of their
country can control the price of gasoline. Her estimate must be
accurate within 2% of the true proportion.
a) No preliminary estimate is available. Find the minimum
sample size needed.
b) Find the minimum sample size needed, using a prior study
that found that 38% of the respondents said they think their
president can control the price of gasoline.
c) Compare...

A researcher wishes to estimate, with 99% confidence, the
population proportion of adults who think the president of their
country can control the price of gasoline. Her estimate must be
accurate within 2% of the true proportion.
a) No preliminary estimate is available. Find the minimum
sample size needed.
b) Find the minimum sample size needed, using a prior study
that found that 32% of the respondents said they think their
president can control the price of gasoline.
c) Compare...

A researcher wishes to estimate, with 95%
confidence, the population proportion of adults who think the
president of their country can control the price of gasoline. Her
estimate must be accurate within 5% of the true proportion.
a) No preliminary estimate is available. Find the minimum
sample size needed.
b) Find the minimum sample size needed, using a prior study
that found that
22%
of the respondents said they think their president can control
the price of gasoline.
c) Compare...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 7 minutes ago

asked 12 minutes ago

asked 26 minutes ago

asked 34 minutes ago

asked 35 minutes ago

asked 35 minutes ago

asked 50 minutes ago

asked 56 minutes ago

asked 58 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago