Question

Assume that we want to come concert De ce este de collected as well as the team starter Question to 1 CA
choice c is incorrect. could someone help me solve this and explain how?

Answer 1

Solution:

Given that

confidence level = c = 90% = 0.90

sample size = n = 53

Since the population standard deviation is unknown , we use t distribution.

(when it is known , we use z distribution)

c = 0.90

$\therefore$$\alpha$ = 1- c = 1- 0.90 = 0.10

$\therefore$  $\alpha$/2 = 0.10 $\slash$ 2 = 0.05

Also, d.f = n - 1 = 53 - 1 = 52

$\therefore$  
ta/2.d.f-
  =  
ta/2.n-1
  =  $url=https://latex.codecogs.com/gif.latex?t&t=1596154678&ymreqid=f4764063-0d40-e2b0-1cde-f00003012f00&sig=nsh.iU8gBt1m17juFlQCGQ--~D$_0.05,52 = 1.674689 = 1.67

(use t table or t value calculator)

Answer is

A.
ta/2.d.f-
= 1.67