When finding critical values, we sometimes need significance levels other than those available in Table. Some computer

Question:

When finding critical values, we sometimes need significance levels other than those available in Table. Some computer programs approximate critical t values by calculating

where d_f= n – 1, e = 2.718, A = z(8 . d_f + 3)>(8 . d_f + 1) and z is the critical z score. Use this approximation to find the critical t score corresponding to n = 150 and a significance level of 0.05 in a right-tailed case. Compare the results to the critical t value of 1.655 found from STATDISK, Minitab, or a TI-83/84 Plus calculator.