Question

The following are body mass index (BMI) scores measured in 12 patients who are free of diabetes and are participating in a study of risk factors for obesity. Body mass index is measured as the ratio of weight in kilograms to height in meters squared. Generate a 95% confidence interval estimate of the true BMI.

25 27      31      33      26   28      38   41   24   32   35      40

Answer 1

We have for given data,              
              
Sample mean =31.67      
Sample standard deviation =5.883  
Sample size =12      
Level of significance=1-0.95=0.05      
Degree of freedom =11      
              
t critical value is (by using t table)=2.201      
              
Confidence interval formula is               


=(27.93, 35.41)          
              
              
Lower confidence limit=27.93  
              
Upper confidence limit=35.41