document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1191026>Question 1191026</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The lengths of pregnancies are normally distributed with a mean of 266 days and a standard deviation of 15 days. \r<BR>\n" );
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document.write( "a. Find the probability of a pregnancy lasting 309 days or longer. <BR>\n" );
document.write( "b. If the length of pregnancy is in the lowest 4​%, then the baby is premature. Find the length that separates premature babies from those who are not premature </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #822889 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=822889\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> z=(x-mean)/sd<BR>\n" );
document.write( "z=(309-266)/15=2.867<BR>\n" );
document.write( "probability z > 2.867 is 0.0021.<BR>\n" );
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document.write( "the lowest 4% from the calculator or the table is -1.751<BR>\n" );
document.write( "-1.751=(x-266)/15<BR>\n" );
document.write( "-26.26=x-266<BR>\n" );
document.write( "x=239.74 days or about 240 days is the cutoff. </SPAN>\n" );
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