The lifetime of a certain brand of battery is known to have a standard deviation of 19.8 hours. Suppose that a random sample of 70 such batteries has a mean lifetime of 39.8 hours. Based on this sample, find a 95% confidence interval for the true mean lifetime of all batteries of this brand. Then give its lower limit and upper limit. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult a list of formulas.) Lower limit:I Upper limit:

The lifetime of a certain brand of battery is known to have a standard deviation of 19.8 hours. Suppose that a random sample of 70 such batteries has a mean lifetime of 39.8 hours. Based on this sample, find a 95% confidence interval for the true mean lifetime of all batteries of this brand. Then give its lower limit and upper limit. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult a list of formulas.) Lower limit:I Upper limit:

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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