For a twotailed test with a 005 significance level what is t

For a two-tailed test with a 0.05 significance level, what is the rejection region when n is large and the population standard deviation is known?

Solution

when n is large and standard deviation is known we can use Z distribution

so using tables of Z distribution

we will find the critical value (Z) for 0.05

critical value : +/- 1.64

rejection region : if Z value is greater than 1.64 or Z value is lower than -1.64