document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=609354>Question 609354</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Colin has pennies, nickels and dimes in his piggybank. He has twice as many nickels as pennies, and he has ten more dimes than nickels. If he has 165 coins altogether, how many dimes does he have? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #384286 by </B><A HREF=/tutors/aboutme.mpl?userid=SwiftAlbatross><B>SwiftAlbatross(13)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=SwiftAlbatross><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=SwiftAlbatross><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=384286\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let p = pennies<BR>\n" );
document.write( "Let n = nickels<BR>\n" );
document.write( "Let d = dimes\r<BR>\n" );
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document.write( "Twice as many nickels as pennies:<BR>\n" );
document.write( "n = 2p\r<BR>\n" );
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document.write( "Ten more dimes than nickels:<BR>\n" );
document.write( "d = n + 10\r<BR>\n" );
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document.write( "165 coins altogether:<BR>\n" );
document.write( "p + n + d = 165\r<BR>\n" );
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document.write( "Now that you have 3 equations and 3 variables, you can solve:<BR>\n" );
document.write( "n = 2p<BR>\n" );
document.write( "d = n + 10<BR>\n" );
document.write( "p + n + d = 165\r<BR>\n" );
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document.write( "Substitute the n value into the other two equations:<BR>\n" );
document.write( "d = 2p + 10<BR>\n" );
document.write( "p + 2p + d = 165  ... which simplifies to ---> 3p + d = 165<BR>\n" );
document.write( " \r<BR>\n" );
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document.write( "You have reduced the number of equations and variables to 2. Keep going:\r<BR>\n" );
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document.write( "Substitute d into the second equation:<BR>\n" );
document.write( "3p + 2p + 10 = 165<BR>\n" );
document.write( "5p + 10 = 165<BR>\n" );
document.write( "5p = 155<BR>\n" );
document.write( "p = 31\r<BR>\n" );
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document.write( "Then plug p back into the other equation<BR>\n" );
document.write( "d = 2(31) + 10<BR>\n" );
document.write( "d = 62 + 10<BR>\n" );
document.write( "d = 72\r<BR>\n" );
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document.write( "Then plug p and d back into one of the original equations:<BR>\n" );
document.write( "p + n + d = 165<BR>\n" );
document.write( "31 + n + 72 = 165<BR>\n" );
document.write( "103 + n = 165<BR>\n" );
document.write( "n = 62\r<BR>\n" );
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document.write( "Check:<BR>\n" );
document.write( "n = 2p<BR>\n" );
document.write( "62 = 2(31)\r<BR>\n" );
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document.write( "d = n + 10<BR>\n" );
document.write( "72 = 62 + 10\r<BR>\n" );
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document.write( "p + n + d = 165<BR>\n" );
document.write( "31 + 62 + 72 = 165\r<BR>\n" );
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document.write( "You're good to go. ^_^ </SPAN>\n" );
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