Question

You intend to estimate a population mean with a confidence interval. You believe the population to have a normal distribution. Your sample size is 7.

Find the critical value that corresponds to a confidence level of 85%.

Answer 1

Answer: C=85%= 0.85 , n=7

Degree of freedom= n-1 = 7-1 =6

Now look into t table as follows to get critical value. Look for row headed df= 6 and column headed C = 0.85 and find corresponding value in body of table as follows.

Thus we get two critical value as follows

Critical value=   1.650 = (- 1.650 , 1.650)