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A random sample of 22 students has an average score of 81 and a standard deviation...

A random sample of 22 students has an average score of 81 and a standard deviation of 9. Form a 95% confidence interval for μ.

Math   Statistics-And-Probability   
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Answer #1

We have given that,              
              
Sample mean =81      
Sample standard deviation =9  
Sample size =22      
Level of significance=1-0.95=0.05      
Degree of freedom =21      
              
t critical value is (by using t table)=   2.08      
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