Question

If σ = 12 then find sample size required to estimate a population mean μ to within 3.6 with 99% confidence?

Answer #1

Solution :

Given that,

standard deviation =s = =12

Margin of error = E = 3.6

At 99% confidence level the z is,

= 1 - 99%

= 1 - 0.99 = 0.01

/2 = 0.005

Z/2 = 2.58

sample size = n = [Z/2* / E] 2

n = ( 2.58*12 /3.6 )2

n =73.96=74

Find the sample size, n, needed to estimate the mean of
a normal population, μ, with σ = 9.25 and a maximum error
of E = 3.2 at a 99% level of confidence.

If σ = 12, find the sample size to estimate the mean
with an error of ±4 and 95 percent confidence (rounded to the next
higher integer).
Multiple Choice
35
75
58
113

Use the given information to find the minimum sample size
required to estimate an unknown population mean μ.
How many students must be randomly selected to estimate the mean
weekly earnings of students at one college? We want 95% confidence
that the sample mean is within $5 of the population mean, and the
population standard deviation is known to be $60.

Assume that a sample is used to estimate a population mean μ.
Find the 99% confidence interval for a sample of size 1107 with a
mean of 32.4 and a standard deviation of 19.7. Enter your answer as
a tri-linear inequality accurate to 3 decimal places.
< μ <

Use the given information to find the minimum sample size
required to estimate an unknown population mean μ.
How many women must be randomly selected to estimate the mean
weight of women in one age group. We want 90% confidence that the
sample mean is within 2.0 lb of the population mean, and the
population standard deviation is known to be 27 lb.

Assume that a sample is used to estimate a population mean μ.
Find the 99% confidence interval for a sample of size 45 with a
mean of 20.1 and a standard deviation of 11.1. Enter your answer as
an open-interval (i.e., parentheses)
accurate to 3 decimal places.
99% C.I. =

Suppose you wish to estimate a population mean μ based on a
sample of n observations. What sample size is required if you want
your estimate to be within 2 of μ with probability equal to 0.95 if
you know the population standard deviation σ is 12?
a. 139 b. 98 c. 127 d. 239 e. 196

Assume that a sample is used to estimate a population mean μ μ .
Find the margin of error M.E. that corresponds to a sample of size
10 with a mean of 17.7 and a standard deviation of 17.6 at a
confidence level of 99.8%. Report ME accurate to one decimal place
because the sample statistics are presented with this accuracy.
M.E. =

a.) Given a normal distribution with σ = 0.380. Find the
required sample size for a 95% confidence level (estimating the
mean), given a margin-of-error of 6%.
b.) Given the sample results taken from a normal population
distribution: mean = 4.65, σ = 0.32, and n = 17.
For a 99% confidence interval, find the margin-of-error for the
population mean. (use 2 decimal places)
c.) Given the sample results taken from a normal population
distribution: mean = 1.25, σ =...

Assume that a sample is used to estimate a population mean μ μ .
Find the 99.5% confidence interval for a sample of size 36 with a
mean of 41.5 and a standard deviation of 15.2. Enter your answer as
an open-interval (i.e., parentheses) accurate to 3 decimal places.
99.5% C.I. = The answer should be obtained without any preliminary
rounding.

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 5 minutes ago

asked 5 minutes ago

asked 5 minutes ago

asked 5 minutes ago

asked 5 minutes ago

asked 5 minutes ago

asked 5 minutes ago

asked 5 minutes ago

asked 7 minutes ago

asked 7 minutes ago

asked 7 minutes ago

asked 7 minutes ago