An auditor reviewed 22 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $270.89 with a standard...

An auditor reviewed 22 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $270.89 with a standard deviation of $76.48.

At the 5 percent level of significance, does this sample prove a violation of the guideline that the average patient should pay no more than $250 out-of-pocket?


(a-1)

H
₀:
μ
≤ $250 versus
H
₁:
μ
> $250. Choose the right option.

1. Reject
   H
   ₀
   if
   t
   _calc
   <>


2. Reject
   H
   ₀
   if
   t
   _calc
   > 1.721

multiple choice 1

• 
  
  
  

  a

  
  
  
  


• 
  
  
  

  b Correct

  
  
  
  

(a-2)
Calculate the test statistic.(Round your answer to 2 decimal places.)


Test statistic



(a-3)
The null hypothesis should be rejected.

multiple choice 2

• 
  
  
  

  False Correct

  
  
  
  


• 
  
  
  

  True

  
  
  
  

(a-4)
The evidence does not show that the average out-of-pocket expense is greater than $250.

multiple choice 3

• 
  
  
  

  True Correct

  
  
  
  


• 
  
  
  

  False

  
  
  
  

(b)
Is this a close decision?

multiple choice 4

• 
  
  
  

  No Correct

  
  
  
  


• 
  
  
  

  Yes