A variable has a mean of 100 and a standard deviation of 16 Four observations of this variable have a mean of 108 and a sample standard deviation of 12 . Determine the observed value of the

a. standardized version of x¯.

b. studentized version of x¯.

Short Answer

Expert verified

Part (a) 1

Part (b) 1.33

Step by step solution

01

Part (a) Step 1: Given information

Sample size n=4

Sample mean x¯=108

Sample s.d., s=12

02

Part (a) Step 2: Concept

The formula used:Z=x¯-μσn,t=x¯-μsn

03

Part (a) Step 3: Calculation

Let the variable xhas meant, μ=100 and s.d., σ=16

A standardized version of x¯,

Z=x¯-μσn=108-100164=816/2=88=1

04

Part (b) Step 1: Calculation

Studentized version of x¯

t=x¯-μsn=108-100124=812/2=86=1.33

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