Question

Find the following:

a. n = 24, area to the right is, .025, t = …….    

                                        

b. df = 30, confidence level is 94%, t = …….

                                        

c.For confidence level 92%, Z= ……..

                                                     

d. If the area to the right is .005, then Z =…….           

Answer 1

Solution:

a)

Using t-distribution table,

t_0.025,23 = 2.069

b)

At 94% confidence level the t is ,

= 1 - 94% = 1 - 0.94 = 0.06

/ 2 = 0.06 / 2 = 0.03

t _/2,df = t_0.03,30 = 1.955

c)

Using standard normal table,

At 92% confidence level the z is ,

= 1 - 92% = 1 - 0.92 = 0.08

/ 2 = 0.08 / 2 = 0.04

Z_/2 = Z_0.04 = 1.751

d)

P(Z > 0.05 ) = 1 - P(z < 0.05)

= 1 - 0.5199 Using standard normal table.

= 0.4801

Area = 0.4801