document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=108307>Question 108307</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Allen bought 30 stamps at the post office in 39¢ and 24¢ denominations. <BR>\n" );
document.write( "If the total cost of the stamps was $9.90, how many 39¢ stamps did Allen buy?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #78947 by </B><A HREF=/tutors/aboutme.mpl?userid=edjones><B>edjones(8007)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=edjones><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=edjones><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=78947\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=amt of .39 stamps and y=amt of .24 stamps.<BR>\n" );
document.write( "A) x+y=30<BR>\n" );
document.write( "B) .39x+.24y=9.9<BR>\n" );
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document.write( "x=30-y<BR>\n" );
document.write( ".39(30-y)+.24y=9.9 Substitute 30-y for x in B).<BR>\n" );
document.write( "11.7-.39y+.24y=9.9<BR>\n" );
document.write( "-.15y+11.7=9.9<BR>\n" );
document.write( "-.15y+11.7-11.7=9.9-11.7<BR>\n" );
document.write( "-.15y=-1.8<BR>\n" );
document.write( "-.15y/-.15=-1.8/-.15<BR>\n" );
document.write( "y=12<BR>\n" );
document.write( "x=30-12<BR>\n" );
document.write( "x=18<BR>\n" );
document.write( "Check:<BR>\n" );
document.write( ".39*18+.24*12=9.9<BR>\n" );
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document.write( "Ed </SPAN>\n" );
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