document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=197132>Question 197132</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A class of 200 students takes an exam. The students' scores are normally distributed with a mean of 72% and a standard deviation of 10. Find the number of students with scores in each interval.\r<BR>\n" );
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document.write( "26.   between 72% and 82%  <BR>\n" );
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document.write( "27.   more than 92%  <BR>\n" );
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document.write( "28.   less than 72%<BR>\n" );
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document.write( "29.   between 62% and 92%  <BR>\n" );
document.write( "about [?]  students </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #147786 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=147786\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A class of 200 students takes an exam. The students' scores are normally distributed with a mean of 72% and a standard deviation of 10. Find the number of students with scores in each interval.<BR>\n" );
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document.write( "I assume you mean that the standard deviation is 10%<BR>\n" );
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document.write( "26.P(between 72% and 82%) = ?<BR>\n" );
document.write( "Since 0.82 is 1 standard deviation to the right of 0.72 the <BR>\n" );
document.write( "percentage of the population that is between those limits is<BR>\n" );
document.write( "34%<BR>\n" );
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document.write( "about[?] students = 0.34*200 = 68<BR>\n" );
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document.write( "27. more than 92%<BR>\n" );
document.write( "0.92 is 3 standard deviations to the right of the mean<BR>\n" );
document.write( "The % of the population to the right of 0.92 is 2.275% <BR>\n" );
document.write( "about[?] students = 0.02275*200 = 4.55<BR>\n" );
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document.write( "28. less than 72%<BR>\n" );
document.write( "50% of the population is to below the mean which is 0.72<BR>\n" );
document.write( "about [?] students = 0.50*200 = 100<BR>\n" );
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document.write( "29. between 62% and 92%<BR>\n" );
document.write( "That would be 2 standard deviations to the left to two std. dev. to the right.<BR>\n" );
document.write( "= 100% - 2(0.02275) = 0.9545 <BR>\n" );
document.write( "about [?] students = 0.9545*200 = approximately 191<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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