document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1095830>Question 1095830</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A consumer survey indicates that the average household spends &#956; =$155 on groceries each week. The distribution of spending amounts is approximately normal with a standard deviation &#963; =$25. Based on this distribution,\r<BR>\n" );
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document.write( "What proportion of the population spends more than $175 per week on groceries?\r<BR>\n" );
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document.write( "How much money do you need to spend on groceries each week to be in the top 20% of the distribution?\r<BR>\n" );
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document.write( "How much does your family spend per week on groceries, what is your family’s percentile? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #710336 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=710336\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> z>(x-mean)/sd<BR>\n" );
document.write( ">(175-155)/25 or >20/25<BR>\n" );
document.write( "that probability is 0.2119<BR>\n" );
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document.write( "top 20% is the 80th percentile, and that z is +0.845<BR>\n" );
document.write( "0.845=(x-155)/25<BR>\n" );
document.write( "multiply by 25 both sides<BR>\n" );
document.write( "x-155=21.13<BR>\n" );
document.write( "x=$176.13 or more<BR>\n" );
document.write( "--------------------- </SPAN>\n" );
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