document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1061628>Question 1061628</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 10. Suppose the random variable X has a normal distribution with mean 9.0 and variance 49. The probability that X takes on a value of at least 18 is approximately equal to\r<BR>\n" );
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document.write( "A. .0985\r<BR>\n" );
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document.write( "B. .4015\r<BR>\n" );
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document.write( "C. .9015\r<BR>\n" );
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document.write( "D. Correct approx. answer not given </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #676576 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=676576\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Variance of 49 leads to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sigma=sqrt%2849%29=7 ALIGN=MIDDLE  ALT=\"sigma=sqrt%2849%29=7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So then the z score of X=18 is,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=z=%2818-9%29%2F7=9%2F7 ALIGN=MIDDLE  ALT=\"z=%2818-9%29%2F7=9%2F7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The probability for this z score is,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%289%2F7%29=0.900729 ALIGN=MIDDLE  ALT=\"P%289%2F7%29=0.900729\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So this is the probability that the score is 18 or less. <BR>\n" );
document.write( "To find the answer, find the complement.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P=1-0.900729 ALIGN=MIDDLE  ALT=\"P=1-0.900729\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P=0.099271 ALIGN=MIDDLE  ALT=\"P=0.099271\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "D. Correct approx. answer not given </SPAN>\n" );
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