A researcher wishes to estimate, with 90% confidence, the population proportion of adults who eat fast food four to six times per week. Her estimate must be accurate within 5% 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 44% of the respondents said they eat fast food four to six times per week. (c) Compare the results from parts (a) and (b). (a) What is the minimum sample size needed assuming that no prior information is available? = (Round up to the nearest whole number as needed.)

A researcher wishes to estimate, with 90% confidence, the population proportion of adults who eat fast food four to six times per week. Her estimate must be accurate within 5% 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 44% of the respondents said they eat fast food four to six times per week. (c) Compare the results from parts (a) and (b). (a) What is the minimum sample size needed assuming that no prior information is available? = (Round up to the nearest whole number as needed.)

Holt Mcdougal Larson Pre-algebra: Student Edition 2012

1st Edition

ISBN:9780547587776

Author:HOLT MCDOUGAL

Publisher:HOLT MCDOUGAL

Chapter11: Data Analysis And Probability

Section: Chapter Questions

Problem 8CR

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