document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=494801>Question 494801</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I'm struggling to calculate this, stats is one of my subjects (long distance learning), but do not understand it. Could you please show me how to calculate the following:\r<BR>\n" );
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document.write( "A normal population has a mean of 75 and a standard deviation of 5.  A sample of size 40 has been randomly selected.  The probability that the sample mean is less than 74 is equal to:\r<BR>\n" );
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document.write( "1. 0.4207<BR>\n" );
document.write( "2. 0.0020<BR>\n" );
document.write( "3. 0.1038<BR>\n" );
document.write( "4. 0.0548<BR>\n" );
document.write( "5. 0.5793 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #335802 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=335802\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A normal population has a mean of 75 and a standard deviation of 5. A sample of size 40 has been randomly selected. The probability that the sample mean is less than 74 is equal to:<BR>\n" );
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document.write( "t(74) = (74-75)/[5/sqrt(40)] = -1.2649<BR>\n" );
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document.write( "P(x-bar < 74) = P(t < -1.2649 when df = 39) = 0.1067<BR>\n" );
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document.write( "If you use the z-distribution you would get:<BR>\n" );
document.write( "P(x-bar < 74) = P(z <-1.2649) = 0.1030<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( " <BR>\n" );
document.write( "1. 0.4207<BR>\n" );
document.write( "2. 0.0020<BR>\n" );
document.write( "3. 0.1038<BR>\n" );
document.write( "4. 0.0548<BR>\n" );
document.write( "5. 0.5793<BR>\n" );
document.write( " </SPAN>\n" );
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