Suppose that the life span of a new calculator is normally distributed with mean 54.4 months and standard deviation 8.2 months. • The company guarantees that any calculator that starts malfunctioning within 36 months of the purchase will be replaced by a new one. What percentage of calculators manufactured by this company are expected to be replaced? • A random sample of 50 calculators is selected. What is the probability that the average lifespan of the calculators in this sample will be greater than 54 months?

Suppose that the life span of a new calculator is normally distributed with mean 54.4 months and standard deviation 8.2 months. • The company guarantees that any calculator that starts malfunctioning within 36 months of the purchase will be replaced by a new one. What percentage of calculators manufactured by this company are expected to be replaced? • A random sample of 50 calculators is selected. What is the probability that the average lifespan of the calculators in this sample will be greater than 54 months?

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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