document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=505144>Question 505144</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If IQ tests have a mean of 100 and standard deviation of 15, what proportion of the population have <BR>\n" );
document.write( "a) an IQ greater than 120, and <BR>\n" );
document.write( "b) an IQ less than 70? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #339821 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=339821\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If IQ tests have a mean of 100 and standard deviation of 15, what proportion of the population have <BR>\n" );
document.write( "a) an IQ greater than 120, <BR>\n" );
document.write( "z(120) = (120-100)/15 = 20/15 = 4/3<BR>\n" );
document.write( "Prop above 120 = P(z > 4/3) = 0.0912<BR>\n" );
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document.write( "and <BR>\n" );
document.write( "b) an IQ less than 70?<BR>\n" );
document.write( "z(70) = (70-100)/15 = -2<BR>\n" );
document.write( "Prop below 70 = P(z < -2) = 0.0228<BR>\n" );
document.write( "=========<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "=========<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );