document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=25889>Question 25889</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please answer the following question:\r<BR>\n" );
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document.write( "  The sum of their ages is 20.  How old is RiRicardo is 4 years less than twice as old as his sister.cardo?  Thanks a million! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #13917 by </B><A HREF=/tutors/aboutme.mpl?userid=smoothflyin><B>smoothflyin(6)</B></A><img src=\"/images/stars/stars-05.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=smoothflyin><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=13917\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> To answer this equation you really just need to assign variables to the various elements. So for instance, we could say that \r<BR>\n" );
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document.write( "R=Ricardo's age<BR>\n" );
document.write( "S=His sister's age\r<BR>\n" );
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document.write( "Ricardo is 4 years less than twice as old as his sister\r<BR>\n" );
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document.write( "So \r<BR>\n" );
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document.write( "R=2S-4\r<BR>\n" );
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document.write( "and we know that the sum of their ages is equal to 20, so\r<BR>\n" );
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document.write( "(R+S=20) and using the commutative property \r<BR>\n" );
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document.write( "(S=20-R)\r<BR>\n" );
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document.write( "So now we plug it back into our original problem (R=2S-4) and we get\r<BR>\n" );
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document.write( "R=2(20-R)-4\r<BR>\n" );
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document.write( "R=40-2R-4\r<BR>\n" );
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document.write( "we bring to 2R over to the other side of the equal sign and change its sign\r<BR>\n" );
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document.write( "3R=40-4 or 3R=36\r<BR>\n" );
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document.write( "divide through by 3 and you get R=12\r<BR>\n" );
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document.write( "Ricardo's age is 12 and his sister's age is 8...Hope this helped! </SPAN>\n" );
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