1) It has been found that times taken by people to complete a particular tax form follow a normaldistribution with a mean of 100 minutes and a standard deviation of 30 minutes. A randomsample of nine people who have completed this tax form was taken.a) What is the probability that the sample mean time taken is less than 85 minutes?b) The probability is 0.01 that the sample standard deviation of time taken is less than howmany minutes?

From the provided information, Mean (µ) = 100 Standard deviation (σ) = 30 X ~N (100, 30) Here X be a…

Answered: 1) It has been found that times taken…

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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A random sample of 28 MBAs working in New York revealed that their mean annual salary was $123,000. Suppose that the population standard deviation σ is $22,000 but that the population mean µ is unknown. What is the point estimate (i.e. the "best guess") of the mean salary µ of all MBAs in this city?
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