document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=771919>Question 771919</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Question 1:<BR>\n" );
document.write( "From past record, 75% of the retirees stated that they preferred living in an apartment to living in a one-family home. A random sample of 30 retirees was taken, and they are asked whether they prefer living in an apartment. 21 of these retirees are responded yes. Construct a 99% confidence interval for the proportion of all retirees who prefer living in an apartment. <BR>\n" );
document.write( "Question 2:<BR>\n" );
document.write( "A survey is being planned to determine the mean amount of time corporation executives watch TV. A survey indicated that the mean time per week is 12 hours with a standard deviation of 3 hours. It is desired to estimate the mean viewing time within one-quarter hour. The 95% level of confidence is to be used. How many executives should be surveyed?  <BR>\n" );
document.write( "Question 3:<BR>\n" );
document.write( "A population is estimated to have a standard deviation of 10. We want to estimate the population mean within 2, with a 95% level of confidence. How large a sample is required?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #470543 by </B><A HREF=/tutors/aboutme.mpl?userid=oscargut><B>oscargut(2103)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=oscargut><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=oscargut><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=470543\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hi,\r<BR>\n" );
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document.write( "I do question 1) here\r<BR>\n" );
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document.write( "CI at 99% is:\r<BR>\n" );
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document.write( "21/30 +-  z(0.005)sqrt((21/30(1-21/30))/30)\r<BR>\n" );
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document.write( "= (0.484,0.916)\r<BR>\n" );
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document.write( "I can help you with more questions at: mthman@gmail.com\r<BR>\n" );
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document.write( "Thanks<BR>\n" );
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