document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=27063>Question 27063</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Andrea is shopping at a bulk store. She needs to buy flour, sudar and salt. She needs twices as much flour as sugar and tic as musch sugar as salt. She plans to buy a total of 10.5 pounds of flour, sugar and salt combined. Flour is $1.20 a pound, sugar is $2.30 a pound, and salt is $.68 a pound. How much of each item will she need to buy and how much will it cost? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #14724 by </B><A HREF=/tutors/aboutme.mpl?userid=mbarugel><B>mbarugel(146)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mbarugel><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=14724\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We must \"translate\" all this data into equations. Let's call A to the amount of flour, B to the amount of sugar, and C to the amount of salt. Now,\r<BR>\n" );
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document.write( "She needs twices as much flour as sugar: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+2B ALIGN=MIDDLE  ALT=\"A+=+2B\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "and twice as much sugar as salt: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=B+=+2C ALIGN=MIDDLE  ALT=\"B+=+2C\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "She plans to buy a total of 10.5 pounds of flour, sugar and salt combined: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%2BB%2BC=10.5 ALIGN=MIDDLE  ALT=\"A%2BB%2BC=10.5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Given these three equations, we can solve the system. First substitute the second one into the first one:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+2%282C%29+=+4C ALIGN=MIDDLE  ALT=\"A+=+2%282C%29+=+4C\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Then we substitute this result into the third one:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4C%2BB%2BC=5C%2BB=10.5 ALIGN=MIDDLE  ALT=\"4C%2BB%2BC=5C%2BB=10.5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Finally, we subsitute again the second one into the one we've just found:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5C%2BB=10.5 ALIGN=MIDDLE  ALT=\"5C%2BB=10.5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5C+%2B+2C+=+7C+=+10.5 ALIGN=MIDDLE  ALT=\"5C+%2B+2C+=+7C+=+10.5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=C+=+10.5%2F7+=+1.5 ALIGN=MIDDLE  ALT=\"C+=+10.5%2F7+=+1.5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "So shw will buy 1.5 pounds of salt. Since she will buy twice as much sugas as salt, she will buy 3 pounds of sugar. And clearly, she will be buy 6 pounds of flour.\r<BR>\n" );
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document.write( "Using the given prices, she will spend:\r<BR>\n" );
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document.write( "6*1.20 + 3*2.30+ 1.5*0.68 = 15.12\r<BR>\n" );
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document.write( "she'll spend $15.12 </SPAN>\n" );
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