document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=548826>Question 548826</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A random sample of  health maintenance organizations (HMOs) was selected. For each HMO, the co-payment (in dollars) for a doctor's office visit was recorded. The results are as follows:   <BR>\n" );
document.write( "9,11,9,7,8,6,11,10,5,12,5,7,6,12,12,9,7,5,10,11\r<BR>\n" );
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document.write( "Under the assumption that co-payment amounts are normally distributed, find a  confidence interval for the mean co-payment amount in dollars. \r<BR>\n" );
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document.write( "Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. \r<BR>\n" );
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document.write( "a)What is the lower limit of the confidence interval?<BR>\n" );
document.write( "b)What is the upper limit of the confidence interval?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #357258 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=357258\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A random sample of health maintenance organizations (HMOs) was selected. For each HMO, the co-payment (in dollars) for a doctor's office visit was recorded. The results are as follows: <BR>\n" );
document.write( "9,11,9,7,8,6,11,10,5,12,5,7,6,12,12,9,7,5,10,11 <BR>\n" );
document.write( "Under the assumption that co-payment amounts are normally distributed, find a confidence interval for the mean co-payment amount in dollars.<BR>\n" );
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document.write( "sample mean = x-bar = :8.6 <BR>\n" );
document.write( "sample std  = s =  2.48<BR>\n" );
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document.write( "Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place.<BR>\n" );
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document.write( "Margin of error if confidence = 95%<BR>\n" );
document.write( "ME = 1.96*2.48/sqrt(20) = 1.087<BR>\n" );
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document.write( "a)What is the lower limit of the confidence interval?:x-bar-ME <BR>\n" );
document.write( "b)What is the upper limit of the confidence interval?:x-bar+ME<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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