document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=631391>Question 631391</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The metal used to make a coin is a mixture of steel and copper.                 The ratio, mass of steel : mass of copper is 108 : 7                            The coin has a total mass of 230 milligrams                                    Calculate the mass of copper in this coin.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #397560 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=397560\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let s represent the mass of steel in the coin<BR>\n" );
document.write( "let c represent the mass of copper in the coin<BR>\n" );
document.write( "the mass in the coin is equal to 230<BR>\n" );
document.write( "your equation is:<BR>\n" );
document.write( "s + c = 230<BR>\n" );
document.write( "since the ratio of steel to copper is 108/7, this means that:<BR>\n" );
document.write( "steel = 108/115 times the mass of the coin.<BR>\n" );
document.write( "copper = 7/115 times the mass of the coin.<BR>\n" );
document.write( "this results in steel = 216 milligrams and copper = 14 milligrams<BR>\n" );
document.write( "the ratio of steel to copper is 216/14 = 108/7<BR>\n" );
document.write( "the sum of the mass of steel and copper is 216 + 14 = 230<BR>\n" );
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document.write( "another way to look at it:<BR>\n" );
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document.write( "the ratio of steel to copper is 108/7<BR>\n" );
document.write( "this means that 108*x + 7*x = mass of the coin.<BR>\n" );
document.write( "this means that 108*x + 7*x = 230<BR>\n" );
document.write( "combine like terms to get:<BR>\n" );
document.write( "115*x = 230<BR>\n" );
document.write( "solve for x to get 2<BR>\n" );
document.write( "this means that 108*2 + 7*2 = 230 which results in:<BR>\n" );
document.write( "216 + 14 = 230 <BR>\n" );
document.write( "this means the mass of the coin in steel is 216 milligrams and the mass of the coin in copper is 14 milligrams.<BR>\n" );
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document.write( "still another way to look at it:<BR>\n" );
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document.write( "ratio of steel to copper is 108/7<BR>\n" );
document.write( "let s represent mass of steel<BR>\n" );
document.write( "let c represent mass of copper<BR>\n" );
document.write( "you get:<BR>\n" );
document.write( "s/c = 108/7<BR>\n" );
document.write( "solve for s to get s = 108c/7<BR>\n" );
document.write( "you also know that s+c = 230<BR>\n" );
document.write( "substitute for s in this equation o get:<BR>\n" );
document.write( "108c/7 + c = 230<BR>\n" );
document.write( "multiply both sides this equation by 7 to get:<BR>\n" );
document.write( "108c + 7c = 230*7<BR>\n" );
document.write( "combine like terms to get:<BR>\n" );
document.write( "115c = 230*7<BR>\n" );
document.write( "divide both sides of this equation by 115 to get:<BR>\n" );
document.write( "c = 230*7/115 which results in c = 14<BR>\n" );
document.write( "since s+c = 230, this means that s must be equal to 216.<BR>\n" );
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