document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=379936>Question 379936</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 7)	The age of student are normally distributed with a mean of 25 and a standard deviation of 4.25. If a student is chosen at random, what is the probability that :<BR>\n" );
document.write( "a)	THE student age is at least 27<BR>\n" );
document.write( "b)	THE student age is between 26 and 30<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 #269703 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=269703\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Here <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=mu+=+25 ALIGN=MIDDLE  ALT=\"mu+=+25\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sigma+=+4.25 ALIGN=MIDDLE  ALT=\"sigma+=+4.25\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "a) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%28X+%3E=+27%29+=+P%28%28X+-+mu%29%2Fsigma+%3E=+%2827+-+25%29%2F4.25+=+0.47%29 ALIGN=MIDDLE  ALT=\"P%28X+%3E=+27%29+=+P%28%28X+-+mu%29%2Fsigma+%3E=+%2827+-+25%29%2F4.25+=+0.47%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  Hence <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%28X+%3E=+27%29+=+P%28Z+%3E=0.47%29 ALIGN=MIDDLE  ALT=\"P%28X+%3E=+27%29+=+P%28Z+%3E=0.47%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "b)  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%2826+%3C+X+%3C+30%29+=+P%28%2826+-+25%29%2F4.25+%3C+%28X+-+mu%29%2Fsigma+=Z+%3C+%2830+-+25%29%2F4.25%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >.  Hence P(26 < X < 30) = P(0.235 < Z < 1.176)\r<BR>\n" );
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document.write( "In either case, just use a usual standard normal table to find the probabilities. </SPAN>\n" );
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