A random sample of 30 households was selected aspart of a study on electricity usage, and the numberof kilowatt-hours (kWh) was recorded for eachhousehold in the sample for the March quarter of2006. The average usage was found to be 375kWh.In a very large study in the March quarter of theprevious year it was found that the standarddeviation of the usage was 81kWh.Assuming the standard deviation is unchanged andthat the usage is normally distributed, provide anexpression for calculating a 99% confidence intervalfor the mean usage in the March quarter of 2006.A375 + 38.0804375 + 28.9854C) 375 ± 30.2425D) 375 ± 40.7571

Given : Sample Size , n= 30 Sample Mean , x̄ =375 population standard deviation , s =81

Answered: A random sample of 30 households was…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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