document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=192056>Question 192056</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can you please help me solve this problem? \r<BR>\n" );
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document.write( " A car dealer thinks it is easier to change spark plugs in Japanese cars than in American cars. They changed a number of spark plugs in each kind of car and the results are given, in minutes below: <BR>\n" );
document.write( "Japabese: 15,21,22,13,18,21,20,21<BR>\n" );
document.write( "American: 19,24,19,16,19,23\r<BR>\n" );
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document.write( "At the 0.05 level of significance, is there sufficient evidence to back his theory?<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 #144122 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=144122\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A car dealer thinks it is easier to change spark plugs in Japanese cars than in American cars. They changed a number of spark plugs in each kind of car and the results are given, in minutes below: <BR>\n" );
document.write( "Japabese: 15,21,22,13,18,21,20,21<BR>\n" );
document.write( "Sample mean = 18.875 ; s = 3.27054<BR>\n" );
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document.write( "American: 19,24,19,16,19,23 <BR>\n" );
document.write( "Sample mean = 20 ; s = 2.96648<BR>\n" );
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document.write( "At the 0.05 level of significance, is there sufficient evidence to back his theory?<BR>\n" );
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document.write( "Ho: u(Jap) - u(Amer) = 0<BR>\n" );
document.write( "H1: u(Jap) - u(Amer) < 0 (Claim)<BR>\n" );
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document.write( "I ran a 2-Sample t test and got the following:<BR>\n" );
document.write( "test statistic: t =-0.6719<BR>\n" );
document.write( "p-value: 0.2575<BR>\n" );
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document.write( "Since the p-value is greater than 5%, fail to reject Ho.<BR>\n" );
document.write( "Replacing one is no faster than replacing the other.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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