document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=188237>Question 188237</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have tried every thing I know how. Can someone help me?<BR>\n" );
document.write( "In Utica, Michigan, 205 of 226 school buses passed the annual safety inspection. In Detroit, Michigan, only 151 of 296 buses passed the inspection. (a) State the hypotheses for a right-tailed test. (b) Obtain a test statistic and p-value. (c) Is normality assured? (d) If significant, is the difference also large enough to be important? (Data are from Detroit Free Press, August 19, 2000, p. 8A.) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #141103 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=141103\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In Utica, Michigan, 205 of 226 school buses passed the annual safety inspection. <BR>\n" );
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document.write( "sample proportion = 205/226 = <BR>\n" );
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document.write( "In Detroit, Michigan, only 151 of 296 buses passed the inspection.<BR>\n" );
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document.write( "sample proportion = 151/296 = <BR>\n" );
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document.write( "(a) State the hypotheses for a right-tailed test.<BR>\n" );
document.write( "Ho: p(utica) - p(detroit) = 0<BR>\n" );
document.write( "Ha; p(utica) - p(detroit) > 0<BR>\n" );
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document.write( "(b) Obtain a test statistic and p-value.<BR>\n" );
document.write( "I ran a 2-PropZTest on a TI calculator and got the following:<BR>\n" );
document.write( "test statistic = z = 9.6491<BR>\n" );
document.write( "p-value: 2.5243x10^-22<BR>\n" );
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document.write( "(c) Is normality assured? <BR>\n" );
document.write( "I'll leave that to you<BR>\n" );
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document.write( "(d) If significant, is the difference also large enough to be important? <BR>\n" );
document.write( "The test provides very strong evidence that the two proportions are not<BR>\n" );
document.write( "equal.  It is large enough to be important.  Utica needs to take some<BR>\n" );
document.write( "action or Detroit need to beef up its inspection criteria..<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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