To determine t2 first determine the value of for a 95 confid

To determine t/2, first determine the value of for a 95% confidence level =0.05 I do not understand critical t values at all. I cant comprehend how they are getting 0.05 as the answer for alpha. Can someone please explain how they are getting this answer?

Solution

we find alpha that is alpha = 1 -0.95 = 0.05

and since is confidence interval we need to divided by 2 because is +/-

alpha /2 = 0.025

but to find the critical value of T we need the degree of freedom that are n-1

n = sample size

that is for T values

for Z values you just need 0.025 and find a value of probability like 0.025

and for that value you will find Z that is in this case 1.96