Question

Determine the t critical value for a two-sided confidence interval in each of the following situations. (Round your answers to three decimal places.)

(a) Confidence level = 95%, df = 5

(b) Confidence level = 95%, df = 15


(c) Confidence level = 99%, df = 15

(d) Confidence level = 99%, n = 10


(e) Confidence level = 98%, df = 21


(f) Confidence level = 99%, n = 34

Answer 1

Solution :

Using t table,

(a)

t _/2,df = 2.571

t critical value = 2.571

(b)

t _/2,df = 2.131

t critical value = 2.131

(c)

t _/2,df = 2.947

t critical value = 2.947

(d)

df = 10 - 1 = 9

t _/2,df = 3.250

t critical value = 3.250

(e)

t _/2,df = 2.518

t critical value = 2.518

(f)

df = 34 - 1 = 33

t _/2,df = 2.733

t critical value = 2.733