document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=297822>Question 297822</A>: <I><SPAN STYLE=\"word-break: break-all;\"> translate the problem into a pair of linear equations in two variables. Solve the equations using either elimination or substitution. State your answer for the specified variable.\r<BR>\n" );
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document.write( "    A sum of money amounting to $3.80 consists of dimes and quarters. If there are 20 coins in all, how many are quarters? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #214406 by </B><A HREF=/tutors/aboutme.mpl?userid=blwinbbbles><B>blwinbbbles(106)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=blwinbbbles><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=blwinbbbles><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=214406\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> so let's first make the equations    x=dimes     y=quarters\r<BR>\n" );
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document.write( "There are x number of dimes and y number of quarters and together the make up 20 coins.\r<BR>\n" );
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document.write( "so  x+y=20  and if dimes are .10 and quarters are .25 then you can say<BR>\n" );
document.write( ".10x + .25y = 3.80\r<BR>\n" );
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document.write( "Now you have the two equations<BR>\n" );
document.write( "1) x + y = 20<BR>\n" );
document.write( "2) .10x + .25y = 3.80<BR>\n" );
document.write( "Let's use substitution and use equation 1, which we can rearrange to say<BR>\n" );
document.write( "x = 20-y  now sub that into x in equation 2\r<BR>\n" );
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document.write( ".10(20-y)+ .25y = 3.80<BR>\n" );
document.write( "2.0 - .10y +.25y = 3.80<BR>\n" );
document.write( "2.0 + .15y = 3.80  subtract 2.0 from both sides<BR>\n" );
document.write( ".15y = 1.80  divide by .15<BR>\n" );
document.write( "y = 12\r<BR>\n" );
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document.write( "so there are 12 quarters...use y = y back into equation 1<BR>\n" );
document.write( "x + 12 = 20  subtract 12 from both sides<BR>\n" );
document.write( "x = 8\r<BR>\n" );
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document.write( "so there are 8 dimes and 12 quarters\r<BR>\n" );
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document.write( " </SPAN>\n" );
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