Question

A statistician believes that the standard deviation of the weights of firemen is less than 25...

A statistician believes that the standard deviation of the weights of firemen is less than 25 pounds. A sample of 20 firemen had a standard deviation of 23.2 pounds. Assume that the variable is normally distributed with  =005 . .

What is the critical value? A) 31.410 B) 30.144 C) 10.851 D) 10.117                   

Test firemen’s claim.                    

i) Null and Alternative Hypotheses                   

ii) Test Statistic                   

iii) Decision

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