A phone manufacturer wishes to estimate the proportion of people who want to purchase a cell phone which costs more than $800. Find the required sample size to yield a 90% confidence interval whose length is below 0.02.
A phone manufacturer wishes to estimate the proportion of people who want to purchase a cell...
15. A phone manufacturer wishes to estimate the proportion of people who want to purchase a cell phone which costs more than $800. Find the required sample size to yield a 90% confidence interval whose length is below 0.02
A tablet PC manufacturer wishes to estimate the proportion of people who want to purchase tablet PCs which cost more than $700. Find the required sample size to yield a 90% confidence interval whose length is below 0.04.
A pollster wishes to estimate, with 95% confidence, the proportion of people who approve of how President Trump is performing his job. Find the minimum sample size necessary to achieve a margin of error of less than 3%. Assuming no previous estimates are available. Round your answer up to the next integer. Assuming a previous estimate of 0.90. Round your answer up to the next integer
A researcher wishes to estimate the proportion of adults who have high-speed Internet access. What size sample should be obtained if she wishes the estimate to be within 0.02 with 90% confidence if a) she uses a previous estimate of 0.34? b) she does not use any prior estimates? a) nequals nothing (Round up to the nearest integer.) b) nequals nothing (Round up to the nearest integer.)
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 3% 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 44% of the respondents said they think their president can control the price of gasoline. c) Compare...
a researcher wishes to estimate the proportion of adults who have high spped internet access . what size sample should be obtained if she wishes the estimate to be within 0.05 with 90% confidence if she uses a previous estimate of 0.46
A researcher wishes to estimate the proportion of adults who have high-speed internet access. What size sample should be obtained if she wishes to estimate to be within 0.02 with 95% confidence if (a) She uses a previous estimate of 0.38? (b) she does not use any prior estimates?
A researcher wishes to estimate the proportion of adults who have high-speed Internet access. What size sample should be obtained if she wishes the estimate to be within 0.02 with 95% confidence if (a) she uses a previous estimate of 0.42? (b) she does not use any prior estimates?
A researcher wishes to estimate the proportion of adults who have high-speed Internet access. What size sample should be obtained if she wishes the estimate to be within 0.01 with 90% confidence if (a) she uses a previous estimate of 0.46? (b) she does not use any prior estimates?
The manufacturer of cell phone batteries wants to estimate the useful life of the battery (in thousands of hours). The estimate is to be within .15 (150) hours. Assume a 95 percent level of confidence and that the standard deviation of the useful life of the battery is 2.00 (2,000) hours. Determine the required sample size. (Round your answer to the next whole number.) Sample size