document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=233773>Question 233773</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A study was conducted to estimate the mean amount spent on birthday gifts for a typical family having two children. A sample of 150 was taken, and the mean amount spent was $225. Assuming a standard deviation equal to $50, find the 95% confidence interval for &#956;, the mean for all such families (show all work).  <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #172623 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=172623\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A study was conducted to estimate the mean amount spent on birthday gifts for a typical family having two children. A sample of 150 was taken, and the mean amount spent was $225. Assuming a standard deviation equal to $50, find the 95% confidence interval for &#956;, the mean for all such families (show all work). <BR>\n" );
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document.write( "sample mean: 225<BR>\n" );
document.write( "standard error: 1.96*50/(sqrt(150) = 8<BR>\n" );
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document.write( "95% CI: 225-8 < u < 225+8<BR>\n" );
document.write( "Ans: (217,233)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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