Do one of the following as appropriate Find the critical val

Do one of the following, as appropriate: Find the critical value^za/z find the critical value ^ta/2, state that neither the normal nor the t distribution applies. 98%; n-7;sigma = 27; population appears to be normally distributed.

Solution

Since the population standard deviation, sigma, is known, then the population mean has a normal distribution, and we will be using the z-score formula for sample means. The test statistic is Z_a/2 = 2.326 ~2.33, Option (D).