A manufacturing firm claims that the batteries used in their electronic games will last an average of 30 hours. To maintain this average, 16 batteries are tested each month. If the computed t-value falls be- tween -to.025 and to.025, the firm is satisfied with its claim. What conclusion should the firm draw from a sample that has a mean of i = 27.5 hours and a stan- dard deviation of s = 5 hours? Assume the distribution of battery lives to be approximately normal.

A manufacturing firm claims that the batteries used in their electronic games will last an average of 30 hours. To maintain this average, 16 batteries are tested each month. If the computed t-value falls be- tween -to.025 and to.025, the firm is satisfied with its claim. What conclusion should the firm draw from a sample that has a mean of i = 27.5 hours and a stan- dard deviation of s = 5 hours? Assume the distribution of battery lives to be approximately normal.

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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