192k views
0 votes
The formula used to compute a confidence interval for the mean of a normal population when n is small is the following. x^^\_ +/-\(t text( critical value)\)s/sqrt(n) What is the appropriate t critical value for each of the following confidence levels and sample sizes? (Round your answers to two decimal places.) (a) 95% confidence, n = 17(b) 90% confidence, n = 12 (c) 99% confidence, n = 24 (d) 90% confidence, n = 24 (e) 80% confidence, n = 13 (f) 95% confidence, n = 10

User Drew Marsh
by
5.8k points

1 Answer

5 votes

Answer:

a) 2.120

b) 1.796

c) 2.807

d) 1.714

e) 1.356

f) 2.262

Explanation:

The formula used to compute a confidence interval for the mean of a normal population when n is small is the following. x^^\_ +/-\(t text( critical value)\)s/sqrt(n) What is the appropriate t critical value for each of the following confidence levels and sample sizes? (Round your answers to two decimal places.)

(a) 95% confidence, n = 17

We find our degrees of freedom first

= n - 1

= 17 - 1

= 16

The t critical value using the t table =

2.120

(b) 90% confidence, n = 12

We find our degrees of freedom first

= n - 1

= 12 - 1

= 11

The t critical value using the t table =

1.796

(c) 99% confidence, n = 24

We find our degrees of freedom first

= n - 1

= 24 - 1

= 23

The t critical value using the t table = 2.807

(d) 90% confidence, n = 24

We find our degrees of freedom first

= n - 1

= 24 - 1

= 23

The t critical value using the t table =

1.714

(e) 80% confidence, n = 13

We find our degrees of freedom first

= n - 1

= 13- 1

= 12

The t critical value using the t table = 1.356

(f) 95% confidence, n = 10

We find our degrees of freedom first

= n - 1

= 10 - 1

= 9

The t critical value using the t table =

2.262

User Karen Tracey
by
5.5k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.