company wants to estimate the time its trucks take to drive from city A to city B. The standard deviation of the data is known to be 12 minutes. The travel time distribution is assumed normal. What sample size is required in order for the error not to exceed ±2 minutes, with 95 percent confidence?

company wants to estimate the time its trucks take to drive from city A to city B. The standard deviation of the data is known to be 12 minutes. The travel time distribution is assumed normal. What sample size is required in order for the error not to exceed ±2 minutes, with 95 percent confidence?

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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