document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=192256>Question 192256</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0618503080/algebrahomeworkh>Intermediate Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> An office has some 20 cent stamps and some 28 cent stamps.  All together the office has 140 stamps for a total value of $31.20.  How many of each stamp does the office have?  \r<BR>\n" );
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document.write( "my try: <BR>\n" );
document.write( "Stamps              Number        Value        Total Value <BR>\n" );
document.write( "20 cent               x             .20           .20x<BR>\n" );
document.write( "28 cent             140 -x          .28           .28(140-x)\r<BR>\n" );
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document.write( ".20x + .28(140-x) = 31.20\r<BR>\n" );
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document.write( ".20x + 39.20 - .28x = 31.20\r<BR>\n" );
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document.write( ".08x + 39.20 = 31.20<BR>\n" );
document.write( "-.08x = -8.00<BR>\n" );
document.write( "x = 1 \r<BR>\n" );
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document.write( "WRONG?   What am I doing wrong??   Help! <BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #144294 by </B><A HREF=/tutors/aboutme.mpl?userid=Mathtut><B>Mathtut(3670)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Mathtut><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=144294\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let the number of 20 cent and 28 cent stamps by x and y respectively<BR>\n" );
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document.write( "x+y=140........eq 1<BR>\n" );
document.write( ".2x+.28y=31.2..eq 2<BR>\n" );
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document.write( "rewrite eq 1 to x=140-y and plug it into eq 2<BR>\n" );
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document.write( ".2(140-y)+.28y=31.2<BR>\n" );
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document.write( "28-.2y+.28y=31.2<BR>\n" );
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document.write( ".08y=3.2<BR>\n" );
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document.write( "y=40 (28 cent stamps)<BR>\n" );
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document.write( "x=140-y=140-40=100 (20 cent stamps) </SPAN>\n" );
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