document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1077770>Question 1077770</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 8.1 #6<BR>\n" );
document.write( "Suppose the lengths of the pregnancies of a certain animal are approximately normally distributed with mean &#956;=176 and &#963;=9 days. \r<BR>\n" );
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document.write( "I know the probability that a randomly selected pregnancy lasts less that 173 days is about 0.3694.\r<BR>\n" );
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document.write( "However, my question is, what is the probability that a sample of 24 pregnancies has a mean gestation period of less than 173 days? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #692293 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=692293\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The std error of 24 pregnancy sample is sd of 9/sqrt (24)=1.837<BR>\n" );
document.write( "z=(x-mean)/1.837, and here the z value is -1.633.<BR>\n" );
document.write( "The probability that the mean of that sample will be < 173 days is 0.0512. </SPAN>\n" );
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