An electric company has been selling a bulb, which was advertised as having an average life of 1,500 hours. Assume that the lifetime of these bulbs is normally distributed with a standard deviation of 800 hours. A random sample of 16 bulbs from this manufacturing process was tested and their lifetimes were recorded. a)What is the probability that the sample mean is between 1, 250 and 1,750 hours? Step by step solution

An electric company has been selling a bulb, which was advertised as having an average life of 1,500 hours. Assume that the lifetime of these bulbs is normally distributed with a standard deviation of 800 hours. A random sample of 16 bulbs from this manufacturing process was tested and their lifetimes were recorded. a)What is the probability that the sample mean is between 1, 250 and 1,750 hours? Step by step solution

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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