1) Construct the confidence interval for the population mean μ.
c=0.98?, x=4.8?, sigmaσequals=0.6, and n=60
A 98?% confidence interval for μ is (___, ___)
(Round to two decimal places as? needed.)
2) A researcher wishes to? estimate, with 95?% ?confidence, the population proportion of adults who say chocolate is their favorite ice cream flavor. Her estimate must be accurate within 4?% 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 22?% of the respondents said their favorite flavor of ice cream is chocolate.
?(c) Compare the results from parts? (a) and? (b).
?(a) What is the minimum sample size needed assuming that no prior information is? available?
n = ______ (Round up to the nearest whole number as? needed.)