Is it possible to reject the null hypothesis without calculating the z-score? We estimated the
Therefore there is a 95% confidence interval between 0.95 (=1.05 - 0.1) and 1.15 (=1.05+0.1)
So we can say we are 95% confident that the μx (of the drug administered rats) is between 0.95 and 1.15. Therefore we can reject the hypothesis because μ of the non-drug-rats is 1.2, which falls outside of the 95%.
Is this reasoning correct?