document.write( "Question 194586: An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $275.66 with a standard deviation of $78.11. (a) 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? State your hypotheses and decision rule. (b) Is this a close decision? \n" ); document.write( "
Algebra.Com's Answer #146253 by stanbon(75887)\"\" \"About 
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An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $275.66 with a standard deviation of $78.11.
\n" ); document.write( "(a) 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? State your hypotheses and decision rule.
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\n" ); document.write( "Ho: u <= 250
\n" ); document.write( "Ha: u > 250.11
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\n" ); document.write( "test statistic: t(275.66) = (275.66-250)/[78.11/sqrt(25)] = 1.6426
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\n" ); document.write( "p-value = P(t > 1.6426 with df = 24) = 0.0568
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\n" ); document.write( "Conclusion:
\n" ); document.write( "Since the p-value is greater than 5%, fail to reject Ho.
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\n" ); document.write( "\n" ); document.write( "(b) Is this a close decision?
\n" ); document.write( "Yes as the p-value is not much greater than 5%.\r
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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