2. The travel time to their workplace of a random sample of workers from thecentral zone of the country is observed in the following frequency table:Minutes15 - 2727393951516363 75Frequency515201510It is assumed that the travel times approximate a normal distribution.Calculate:a) A 90% confidence interval for the population average of travel times.b) A 90% confidence interval for the population standard deviation.

MinutesFrequency15 to 27527 to 391539 to 512051 to 631563 to 7510Sum65

Answered: 2. The travel time to their workplace…

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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