document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=669400>Question 669400</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Joe has a collection of nickels and dimes that is worth $5.65. If the number of dimes were doubled and the number of nickels were increased by 8, the value of the coins would be $10.45. How many dimes does he have?    \r<BR>\n" );
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document.write( "This is the problem directly from my homework.  I'm trying to figure out the system of equations so I can solve the problem.  So far I've come up with\r<BR>\n" );
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document.write( "	.1d+.05n=5.65       and               2(.1d)+.05n+8=10.45\r<BR>\n" );
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document.write( "but I keep ending up with d= -32 so I must be way off. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #416391 by </B><A HREF=/tutors/aboutme.mpl?userid=MathTherapy><B>MathTherapy(10552)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathTherapy><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=MathTherapy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=416391\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "Joe has a collection of nickels and dimes that is worth $5.65. If the number of dimes were doubled and the number of nickels were increased by 8, the value of the coins would be $10.45. How many dimes does he have?    \r<BR>\n" );
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document.write( "This is the problem directly from my homework.  I'm trying to figure out the system of equations so I can solve the problem.  So far I've come up with\r<BR>\n" );
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document.write( "	.1d+.05n=5.65       and               2(.1d)+.05n+8=10.45\r<BR>\n" );
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document.write( "but I keep ending up with d= -32 so I must be way off.\r<BR>\n" );
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document.write( "You are off, but not by that much. Looking at what I got and you got, I can see that your 2nd equation should have been .1(2D) + .05(N + 8) = 10.45. This is where your error is. The correct solution is below:\r<BR>\n" );
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document.write( "Let the original amount of dimes and nickels that he has be D, and N, respectively<BR>\n" );
document.write( "Then: .1D + .05N = 5.65 ----- eq (i)<BR>\n" );
document.write( "Doubling the amount of dimes would make the dimes, 2D<BR>\n" );
document.write( "Increasing the nickels by 8 would make the amount of nickels, N + 8 <BR>\n" );
document.write( "Therefore, .1(2D) + .05(N + 8) = 10.45 ------ .2D + .05N + .4 = 10.45 ---- .2D + .05N = 10.05 ----- eq (ii)\r<BR>\n" );
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document.write( ".1D + .05N = 5.65 ---- eq (i)<BR>\n" );
document.write( ".2D + .05N = 10.05 ---- eq (ii) <BR>\n" );
document.write( "- .1D = - 4.40 --------- Subtracting eq (ii) from eq (i)<BR>\n" );
document.write( "D, or original amount of dimes = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-+4.4%29%2F-+.1 ALIGN=MIDDLE  ALT=\"%28-+4.4%29%2F-+.1\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%2844%29 ALIGN=MIDDLE  ALT=\"highlight_green%2844%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Send comments and “thank-yous” to “D” at MathMadEzy@aol.com </SPAN>\n" );
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