Question

find the critical value for the given confidence level c and sample size n c=.90 n=21

Answer 1

The critical value for the given confidence level, c = 0.90 and n = 21 is $t_c=1.725$.

How to calculate the critical value for t-distribution?

The critical value is calculated as follows:

• For the given sample size n, find the degree of freedom (d.f)
• Where d.f = n - 1
• Using the t-distribution table, the critical value is obtained for the obtained d.f and the confidence level.

Calculation:

It is given that,

confidence level c = 0.90

sample size n = 21

Then,

degree of freedom,

(d.f) = n - 1 = 21 - 1 = 20

So, from the t-distribution table,

at d.f = 20 and the confidence level 0.90, the critical value is 1.725.

I.e., $t_c$ = 1.725

For this, α = (1 - 0.90)/2 = 0.05

Learn more about the critical value here:

https://brainly.com/question/28151908

#SPJ1