document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=136316>Question 136316</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A Cell phone company offers two plans to its subscribers. At the time new subscribers sign up they are asked to provide some demographic information. The mean yearly income for a sample of 42 subscribers to plan A is $57,000 with a standard Deviation of $6,000. For a sample of 50 subscribers to plan B the mean income is $63,000 with a standard deviation of $4,900. At a significance of 0.05 is there a difference in between the two plans? \r<BR>\n" );
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document.write( "Ho <BR>\n" );
document.write( "H1<BR>\n" );
document.write( "Alpha: <BR>\n" );
document.write( "CV:<BR>\n" );
document.write( "What Formula? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #99847 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=99847\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A Cell phone company offers two plans to its subscribers. At the time new subscribers sign up they are asked to provide some demographic information. <BR>\n" );
document.write( "The mean yearly income for a sample of 42 subscribers to plan A is $57,000 with a standard Deviation of $6,000. <BR>\n" );
document.write( "For a sample of 50 subscribers to plan B the mean income is $63,000 with a standard deviation of $4,900. <BR>\n" );
document.write( "At a significance of 0.05 is there a difference in between the two plans? <BR>\n" );
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document.write( "Comment: I don't think you are comparing plans; you are comparing income<BR>\n" );
document.write( "of plan purchasers.<BR>\n" );
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document.write( "Ho: u(A)=u(B) <BR>\n" );
document.write( "H1: u(A) is not equal to u(B)<BR>\n" );
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document.write( "Alpha:5%<BR>\n" );
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document.write( "CV:+-1.96<BR>\n" );
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document.write( "What Formula?<BR>\n" );
document.write( "Test statistic for 2-Sample T-test: <BR>\n" );
document.write( "t(57000-63000) = (-6000)/sqrt[(6000^2/42)+(4900^2/50)]=-5.188..<BR>\n" );
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document.write( "Conclusion: since test stat is in the rejection interval, Reject Ho.<BR>\n" );
document.write( "Income of plan A and plan B purchasers are not the same.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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