Question

Consider a right-tailed test (upper tail) and a sample size of 40 at the 95% confidence level. The value of t is ________.
a. +2.023
b. -2.023
c. -1.685
d. +1.685

Answer 1

Answer:

The correct option is d.

Step-by-step explanation:

The directional hypothesis is:

$H_{a}:\mu>\mu_{0}$

The sample size is, n = 40.

The significance level is:

$\alpha =1-0.95=0.05$

Use the t-table to compute the right-tailed t-critical value as follows:

$t_{\alpha,\ (n-1)}=t_{0.05, (40-1)}$

             $=t_{0.05, 39}\\\\\approx t_{0.05, 40}\\\\=1.684\\\\\approx 1.685$

The value is positive since the directional hypothesis suggests that the test is right tailed.

The correct option is d.