Barron's reported that the average number of weeks an individual is unemployed is 17.5 weeks (Barron's}, February 18, 2008). Assume that for the population of all unemployed individuals, the population mean length of unemployment is 17.5 weeks and that the population standard deviation is 4 weeks. Suppose you would like to select a random sample of 50 unemployed individuals for a follow-up study. (a) What is the probability that a sample of 50 unemployed individuals will provide a sample mean more than 20 weeks? (b) What is the probability that a sample of 50 unemployed individuals will provide a sample mean within 1 week of the population mean?

Barron's reported that the average number of weeks an individual is unemployed is 17.5 weeks (Barron's}, February 18, 2008). Assume that for the population of all unemployed individuals, the population mean length of unemployment is 17.5 weeks and that the population standard deviation is 4 weeks. Suppose you would like to select a random sample of 50 unemployed individuals for a follow-up study. (a) What is the probability that a sample of 50 unemployed individuals will provide a sample mean more than 20 weeks? (b) What is the probability that a sample of 50 unemployed individuals will provide a sample mean within 1 week of the population mean?

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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