4. The lifetime of an electronic component follows a normal distribution with a mean of 38 hours and a standard deviation of 2.5 hours. A shipment of 2000 of such components is delivered to a factory. a) Approximately how many of these components will last between 35 to 40 hours? (2pts) b) A randomly selected component lasts longer than 34% of all other components, what is the lifetime of this component? (2pts) c) If we randomly select 10 components from this shipment, what is the probability that the average of these components is less than 37.5 hours? (2pts)

4. The lifetime of an electronic component follows a normal distribution with a mean of 38 hours and a standard deviation of 2.5 hours. A shipment of 2000 of such components is delivered to a factory. a) Approximately how many of these components will last between 35 to 40 hours? (2pts) b) A randomly selected component lasts longer than 34% of all other components, what is the lifetime of this component? (2pts) c) If we randomly select 10 components from this shipment, what is the probability that the average of these components is less than 37.5 hours? (2pts)

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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