document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1159076>Question 1159076</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The speed limit on I-25 in Colorado was raised to 75mph in certain sections in 2002. The speed of 144 cars passing a checkpoint in one of these sections was collected this year. It was found that the cars were traveling with a mean speed of 80mph with a standard deviation of 3mph.\r<BR>\n" );
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document.write( "Conduct a hypothesis test at α=0.05 level of significance to see if this is enough evidence to show that drivers are still speeding (more than 75mph) on these sections of highway.\r<BR>\n" );
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document.write( "What is the appropriate hypothesis? \r<BR>\n" );
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document.write( "Perform the test using either the critical value method or the p-value method. \r<BR>\n" );
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document.write( "State the conclusion of the test and interpret it.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #782254 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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/cgi-bin/show-face.mpl?user=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=782254\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Ho: speed 75 mph or less<BR>\n" );
document.write( "Ha: speed > 75 mph<BR>\n" );
document.write( "alpha=0.05 P{rejectHo|Ho true}<BR>\n" );
document.write( "test is a t ((0.95,df=143) with a critical value of t>1.656<BR>\n" );
document.write( "t=(x bar-mean)/s/sqrt(n)<BR>\n" );
document.write( "=5*sqrt(144)/3<BR>\n" );
document.write( "=20 highly significant for the speed being >75 mph with p value<< 0.0001 </SPAN>\n" );
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