document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=609947>Question 609947</A>: <I><SPAN STYLE=\"word-break: break-all;\"> assume that a school district has 10,000 6th graders. in the district, the average weight of a 6th grader is 80 pounds, with a standard deviation of 20 pounds. suppose you draw a random sample of 50 students. what is the probability that the average weight of a sampled student will be between 75 and 105 pounds? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #384034 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=384034\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> assume that a school district has 10,000 6th graders. in the district, the average weight of a 6th grader is 80 pounds, with a standard deviation of 20 pounds. suppose you draw a random sample of 50 students. what is the probability that the average weight of a sampled student will be between 75 and 105 pounds?<BR>\n" );
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document.write( "z(75) = (75-80)/[20/sqrt(50)] = -1.7678<BR>\n" );
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document.write( "z(105) = (105-80)/[20/sqrt(50)] = 8.8388<BR>\n" );
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document.write( "P(75 <= x-bar <= 105) = P(-1.7678 <= z <= 8.8388) = 0.9615<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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