document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=614691>Question 614691</A>: <I><SPAN STYLE=\"word-break: break-all;\"> For a normal population with population = 70 and population standard deviation = 20, what is the probability of obtaiing a sample mean equal to or greater than 75 for a random sample of n= 225? How do you arrive at the probability by reporting the standard error and the z-score? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #386704 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=386704\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> For a normal population with population with u = 70 and population standard deviation = 20, what is the probability of obtaining a sample mean equal to or greater than 75 for a random sample of n= 225? How do you arrive at the probability by reporting the standard error and the z-score?<BR>\n" );
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document.write( "mean of the sample means = 70<BR>\n" );
document.write( "std of the sample means = 20/sqrt(225) = 20/15 = 4/3<BR>\n" );
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document.write( "z(75) = (75-70)/15 = 5/15 = 1/3<BR>\n" );
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document.write( "P(x-bar > 75) = P(z > 1/3) = normalcdf(1/3,100) = 0.3694<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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