document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=885586>Question 885586</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello - Can you assist me on the second part of this statistic question?\r<BR>\n" );
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document.write( "Part one: The mean television viewing time for teens is 3 hours per day. Assume  = 3 and population standard deviation is  = 1.2 hours. Suppose a sample of 50 teens will be used to monitor television viewing time. What is the probability the sample mean will be within  0.25 hours of the population mean?  I was able to calculate the answer to be = 0.8584.\r<BR>\n" );
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document.write( "The second part of the problem is: Reference television viewing problem statement, what is the probability the sample mean will be less than 2.7 hours?  \r<BR>\n" );
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document.write( "Thank you for your help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #535321 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=535321\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> you got the first part correct.<BR>\n" );
document.write( "for the second part:<BR>\n" );
document.write( "pm = population mean<BR>\n" );
document.write( "psd = population standard deviation<BR>\n" );
document.write( "n = sample size<BR>\n" );
document.write( "sm = sample mean<BR>\n" );
document.write( "se = standard error\r<BR>\n" );
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document.write( "in this problem:<BR>\n" );
document.write( "pm = 3<BR>\n" );
document.write( "psd = 1.2<BR>\n" );
document.write( "sm = 2.7<BR>\n" );
document.write( "n = 50<BR>\n" );
document.write( "se = psd / sqrt(n) = 1.2 / sqrt(50) = .1697<BR>\n" );
document.write( "z = (sm - pm) / se = (2.7 - 3) / .1697 = -.3 / .1697 = -1.77\r<BR>\n" );
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document.write( "from the z score table, area to the left of -1.77 = .0384\r<BR>\n" );
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document.write( "since you want to know the probability of getting a sample mean less than 2.7 hours, you want the area to the left of the z score.\r<BR>\n" );
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document.write( "your answer is that the probability is equal to .0384.\r<BR>\n" );
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document.write( "the z score table i used can be found here:<BR>\n" );
document.write( "<a hrer = \"http://lilt.ilstu.edu/dasacke/eco148/ztable.htm\" target = \"_blank\">http://lilt.ilstu.edu/dasacke/eco148/ztable.htm</a>\r<BR>\n" );
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document.write( " </SPAN>\n" );
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