document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1050168>Question 1050168</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The length of human pregnancies from conception to birth varies according to a distribution that is approximately Normal with mean 266 days and standard deviation 16 days. What is the probability that the average pregnancy length for six randomly chosen women exceeds 270 days?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #665758 by </B><A HREF=/tutors/aboutme.mpl?userid=ewatrrr><B>ewatrrr(24785)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ewatrrr><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=ewatrrr><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=665758\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=z+=blue+%28x+-+mu%29%2Fblue%28sigma%2Fsqrt%28n%29%29 ALIGN=MIDDLE  ALT=\"z+=blue+%28x+-+mu%29%2Fblue%28sigma%2Fsqrt%28n%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "P(x>270) = 1 - P(<=270) = 1- P(z<= (270-266)/(16/sqrt(6)) =  1- P(z<= .6124)<BR>\n" );
document.write( "P(z<= .6124) = .73<BR>\n" );
document.write( "P(x>270) = 1- P(z<= .6124) = 1 -.73 = .27 </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );