Suppose the life of a particular brand of calculator battery is approximately normally distributed with a mean of 80 hours and a standard deviation of 9 hours. Complete parts a through c. a. What is the probability that a single battery randomly selected from the population will have a life between 70 and 90 hours? P(70≤x≤90)=0.7286 (Round to four decimal places as needed.)

Suppose the life of a particular brand of calculator battery is approximately normally distributed with a mean of 80 hours and a standard deviation of 9 hours. Complete parts a through c. a. What is the probability that a single battery randomly selected from the population will have a life between 70 and 90 hours? P(70≤x≤90)=0.7286 (Round to four decimal places as needed.)

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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