Question

Find the t_a/2 value for a 95% confidence interval when the sample size is 22.

Answer 1

For a confidence level of 95%, we know that $\alpha = 1 - 0.95 = 0.05$ and a sample size of $n = 22,$ we get $df = 22-1 =21$ degrees of freedom, and using a t-distribution table we find that 

$$t_{\alpha/2, n-1}=t_{0.025, 21}= 2.079614$$