Question

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 $281.54 with a standard deviation of $77.58.

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)	H0: μ ≤ $250 versus H1: μ > $250. Choose the right option.

a.	Reject H0 if p > 0.05
b.	Reject H0 if p < 0.05

	a
	b

(a-2)

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

Test statistic

Answer 1

Solution :

= 250

=281.54

=77.58

n = 22

This is the right tailed test .

The null and alternative hypothesis is ,

H0 :    =250

Ha : > 250

Test statistic = z

= ( - ) / / n

= (281.54 - 250) / 77.58 / 22

= 1.907

Test statistic = z= 1.907

P-value =0.0283

= 0.05  

P-value <

0.0283 < 0.05

Reject the null hypothesis .

There is sufficient evidence to suggest that