Testing Mean with known Variance
sample size9
population variance2
sample mean-4
null hypothesis about mean0
type I error0.05
critical value (one-tailed)-0.775391435784449
confidence interval (two-tailed)
(sample mean)
[ -4.92393588289979 , -3.07606411710021 ]
conclusion for one-tailed test
Reject the null hypothesis.
conclusion for two-tailed test
Reject the null hypothesis