document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=720784>Question 720784</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help.  I have tried to find similar problems and work this out but I have only confused myself more.  Thank you, it is the only one I haven't been able to answer and it is due 3/2/13.\r<BR>\n" );
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document.write( "Assume that the population of heights of male college students is approximately normally distributed with mean u of 69.66 inches and standard deviation o of 6.08 inches. A random sample of 84 heights is obtained.  Show all work. <BR>\n" );
document.write( "(A)  Find P(x>68.75)<BR>\n" );
document.write( "(B)  Find the mean and standard error of the x-bar distribution <BR>\n" );
document.write( "(C)  Find P(x-bar>68.75)<BR>\n" );
document.write( "(D)  Why is the formula required to solve (A) different than (C)? <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #441976 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=441976\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Assume that the population of heights of male college students is approximately normally distributed with mean u of 69.66 inches and standard deviation o of 6.08 inches. A random sample of 84 heights is obtained. Show all work. <BR>\n" );
document.write( "(A) Find P(x > 68.75)<BR>\n" );
document.write( "z(68.75) = (68.75-69.66)/6.08] = -0.1497<BR>\n" );
document.write( "P(x > 68.75) = P(z > -0.1497) = normalcdf(-0.1497,100) = 0.5595<BR>\n" );
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document.write( "(B) Find the mean and standard error of the x-bar distribution<BR>\n" );
document.write( "mean = 69.66 ; std = 6.08/sqrt(84) = 0.6634<BR>\n" );
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document.write( "(C) Find P(x-bar>68.75)<BR>\n" );
document.write( "P(x-bar > 68.75)<BR>\n" );
document.write( "z(68.75) = (68.75-69.66)/[6.08/sqrt(84)] = -1.3718<BR>\n" );
document.write( "P(x-bar) > 68.75) = P(z > -1.3718) = normalcdf(-1.3718,100) = 0.9149\r<BR>\n" );
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document.write( "(D) Why is the formula required to solve (A) different than (C)?<BR>\n" );
document.write( "The Central Limit Theorem explains that.<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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