document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1176498>Question 1176498</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The average math SAT score is 511 with a standard deviation of 199. A particular high school calims that its students have unusually high math SAT scores. A random sample of 40 students from this school was selected, and the mean math SAT score was 555. Is the high school justified in its claim? Explain?\r<BR>\n" );
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document.write( "Find the Z-score and complete the explanation/statement\r<BR>\n" );
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document.write( "(Yes/No) because the z-score ([?]) is (unusual/not unusual) since it (lies / does not lie) within the range of a usual event, namely within (1,2,3 standard deviation) of the mean of the sample means.\r<BR>\n" );
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document.write( "(Round to two decimal places as needed)\r<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 #803567 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=803567\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the z-score is z=(x bar-mean)/sigma/sqrt(n)<BR>\n" );
document.write( "=(555-511)/199/sqrt(40)<BR>\n" );
document.write( "=44*sqrt(40)/199<BR>\n" );
document.write( "=1.40<BR>\n" );
document.write( "The probability of finding a result this much or more extreme is 0.0810<BR>\n" );
document.write( "It depends upon what criteria the tester wants to require from the school.<BR>\n" );
document.write( "If the 5% level of significance is used, which would be (for a 1 way test) 1.645 or more sd s from the sample mean, then no, it is not unusual.  If the 10% level is used, then it would be unusual.<BR>\n" );
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