document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1010581>Question 1010581</A>: <I><SPAN STYLE=\"word-break: break-all;\"> To profitably produce a planned upgrade of a software product you make, you must charge customers $100. Are your customers willing to pay this much? You contact a random sample of 40 customers and find 11 would pay $100 for the upgrade. If the upgrade is to be profitable, you will need to sell it to more than 20% of your customers. Do the sample data give good evidence that more than 20% are willing to buy?\r<BR>\n" );
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document.write( " Include the following elements in your test.\r<BR>\n" );
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document.write( "Hypotheses (3 pts)\r<BR>\n" );
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document.write( "Model (4 pts) Note which condition is not met, but continue with the test anyway.\r<BR>\n" );
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document.write( "Mechanics (5 pts)\r<BR>\n" );
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document.write( "Conclusion (4 pts)<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 #626023 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=626023\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  To profitably produce a planned upgrade of a software product you make, you must charge customers $100. Are your customers willing to pay this much? You contact a random sample of 40 customers and find 11 would pay $100 for the upgrade. If the upgrade is to be profitable, you will need to sell it to more than 20% of your customers. Do the sample data give good evidence that more than 20% are willing to buy? <BR>\n" );
document.write( "Include the following elements in your test. <BR>\n" );
document.write( "Hypotheses (3 pts)<BR>\n" );
document.write( "Ho: p <= 0.2<BR>\n" );
document.write( "Ha: p > 0.2 (claim)<BR>\n" );
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document.write( "p-hat = 11/40 = 0.275<BR>\n" );
document.write( "test stat:: z(0.275) = (0.275-0.2)/sqrt[0.275*0.725/40] = 1.0632<BR>\n" );
document.write( "p-value = P(z > 1.0632) = 0.1440<BR>\n" );
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document.write( "Since the p-value is greater than 5%, fail ro reject Ho.<BR>\n" );
document.write( "The test results do not support the claim.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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