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% 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 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) (b) What is 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? n= (Round up to the nearest whole number as needed.) (c) How do the results from (a) and (b) compare? O A Having an estimate of the population proportion reduces the minimum sample size needed OB. Having an estimate of the population proportion raises the minimum sample size needed. O C. Having an estimate of the population proportion has no effect on the minimum sample size needed

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% 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 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) (b) What is 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? n= (Round up to the nearest whole number as needed.) (c) How do the results from (a) and (b) compare? O A Having an estimate of the population proportion reduces the minimum sample size needed OB. Having an estimate of the population proportion raises the minimum sample size needed. O C. Having an estimate of the population proportion has no effect on the minimum sample size needed

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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