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Z test for population mean

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1. A battery was designed to last an average of 30 hours in a radio. Complaints are pouring in that the batteries are junk and do not perform as expected. You test 24 batteries and find :
X = 29.3
S = 2.95
Normality assumed
Is there sufficient evidence to indicate premature battery failure at the &#61537; = .05 level?

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Hypothesis Testing (Z- Testing)
1. A battery was designed to last an average of 30 hours in a radio. Complaints are pouring in that the batteries are junk and do not perform as expected. You test 24 batteries and find :
X = 29.3
S = 2.95
Normality assumed
= .05 ...

Solution Summary

The solution provides step by step method for the calculation of Z test statistic and P value . Formula for the calculation and Interpretations of the results are also included.

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