Question

Men diagnosed with cancer were randomly assigned to either undergo surgery or not. Among the 333 men who had the​ surgery, 15 eventually died of​ cancer, compared with 32 of the 335 men who did not have surgery. ​a) Was this an experiment or an observational​ study? Explain. ​b) Create a 90​% confidence interval for the difference in rates of death for the two groups of men. ​c) Based on your confidence​ interval, is there evidence that surgery may be effective in preventing death from​ cancer? Explain. ​a) Choose the correct answer below. A. Observational study because an observation was made about men diagnosed with cancer. B. Observational study because men were randomly assigned to have surgery or not. C. Experiment because men were randomly assigned to have surgery or not. D. Experiment because an observation was made about men diagnosed with cancer. ​b) Let ModifyingAbove p with caret 1 be the sample proportion of men who did not have surgery and​ died, and let ModifyingAbove p with caret 2 be the sample proportion of men who had surgery and died. Create a 90​% confidence interval for the difference in rates of death for the two groups of​ men, p 1minusp 2. left parenthesis nothing comma nothing right parenthesis ​(Round to three decimal places as​ needed.) ​c) Based on your confidence​ interval, is there evidence that surgery may be effective in preventing death from​ cancer? Since th

Answer 1