Question

How large a sample should be selected to provide a 95% confidence interval with a margin...

How large a sample should be selected to provide a 95% confidence interval with a margin of error of 4? Assume that the population standard deviation is 30 . Round your answer to next whole number.

Homework Answers

Answer #1

Solution :

Given that,

standard deviation = = 30

margin of error = E = 4

At 95% confidence level the z is ,

= 1 - 95% = 1 - 0.95 = 0.05

/ 2 = 0.05 / 2 = 0.025

Z/2 = Z0.025 = 1.960

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

= ((1.960 * 30) / 4 )2

= 216.09

= 216

Sample size = 216

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
At 95% confidence, how large a sample should be taken to obtain a margin of error...
At 95% confidence, how large a sample should be taken to obtain a margin of error of 0.026 for the estimation of a population proportion? Assume that past data are not available for developing a planning value for p*. Round up to the next whole number.
At 95% confidence, how large a sample should be taken to obtain a margin of error...
At 95% confidence, how large a sample should be taken to obtain a margin of error of .015 for the estimation of a population proportion? Assume that past data are not available for developing a planning value for P* . Round up to the next whole number.
At 99% confidence, how large a sample should be taken to obtain a margin of error...
At 99% confidence, how large a sample should be taken to obtain a margin of error of .012 for the estimation of a population proportion? Assume that past data are not available for developing a planning value for p*. Round up to the next whole number.
At 99% confidence, how large a sample should be taken to obtain a margin of error...
At 99% confidence, how large a sample should be taken to obtain a margin of error of 0.041 for the estimation of a population proportion? Assume that past data are not available for developing a planning value for p* . Round up to the next whole number.
In a survey, the planning value for the population proportion is p*=.25 . How large a...
In a survey, the planning value for the population proportion is p*=.25 . How large a sample should be taken to provide a 95% confidence interval with a margin of error of .06? Round your answer to next whole number.
What sample size would be needed to construct a 95% confidence interval with a 5% margin...
What sample size would be needed to construct a 95% confidence interval with a 5% margin of error on any population proportion? Give a whole number answer. (Of course.)
In a survey, the planning value for the population proportion is p* = 0.26. How large...
In a survey, the planning value for the population proportion is p* = 0.26. How large a sample should be taken to provide a 95% confidence interval with a margin of error of 0.05? (Round your answer up to nearest whole number.)
In a survey, the planning value for the population proportion is p* = 0.31. How large...
In a survey, the planning value for the population proportion is p* = 0.31. How large a sample should be taken to provide a 95% confidence interval with a margin of error of 0.05? (Round your answer up to nearest whole number.)
Find the margin of error for a​ 95% confidence interval for estimating the population mean when...
Find the margin of error for a​ 95% confidence interval for estimating the population mean when the sample standard deviation equals 90 with a sample size of​ (i) 484 and​ (ii) 1600 ​(i) Find the margin of error for a​ 95% confidence interval for estimating the population mean when the sample standard deviation equals 90 with a sample size of 484 (ii). ​(ii) Find the margin of error for a​ 95% confidence interval for estimating the population mean when the...
(S 9.2) Recall that a confidence interval for the sample mean can be calculated using the...
(S 9.2) Recall that a confidence interval for the sample mean can be calculated using the interval x¯?tn?1?sn??????x¯+tn?1?sn??? Thus, the margin of error is tn?1?sn??? We can recover the margin of error from an interval constructed on the calculator using algebra. Suppose a random sample of size 16 was taken from a normally distributed population, and the sample standard deviation was calculated to be s = 6.3. We'll assume the sample mean is 10 for convenience. a) Calculate the margin...