document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=510117>Question 510117</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 9.	Household income does not tend to follow a normal distribution in a particular state, yet average income is approximately $45,000/year in this state, with a standard deviation of about $9000. Within what income range would approximately 93.75% of the household incomes lie within this state? Show all work as to how this is obtained.\r<BR>\n" );
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document.write( "Can someone please help me with this, I don't know what to do at all.  I need some explanation please </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #341749 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=341749\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Household income does not tend to follow a normal distribution in a particular state, yet average income is approximately $45,000/year in this state, with a standard deviation of about $9000.<BR>\n" );
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document.write( " Within what income range would approximately 93.75% of the household incomes lie within this state? Show all work as to how this is obtained. <BR>\n" );
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document.write( "Draw the picture of a normal curve with 93.75% centered on the mean.<BR>\n" );
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document.write( "The two tails = 1- 0.9374 = 0.0626<BR>\n" );
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document.write( "The left tail is 0.0626/2 = 0.0313<BR>\n" );
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document.write( "Find the z-value with a left tail of 0.0313<BR>\n" );
document.write( "z = invNorm(0.0313) = -1.8620<BR>\n" );
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document.write( "Find the corresponding income value:<BR>\n" );
document.write( "x = zs + u<BR>\n" );
document.write( "x = -1.8620*9000 + 45000 = $28,242.00<BR>\n" );
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document.write( "Similarly the upper income level is<BR>\n" );
document.write( "x = +1.8620*9000 + 45000 = $61,758<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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