document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1167887>Question 1167887</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Ari is 3 times as old as Ben now. In 6 years' time, the total age of Ari and Ben will be 84 years. How old will Ben be in 6 years' time? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #792501 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=792501\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "By formal algebra....<br><BR>\n" );
document.write( "x = Ben's age now<BR>\n" );
document.write( "3x = Ari's age now<BR>\n" );
document.write( "x+6 = Ben's age 6 years from now<BR>\n" );
document.write( "3x+6 = Ari's age 6 years from now<br><BR>\n" );
document.write( "The sum of their ages 6 years from now will be 84:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x%2B6%29%2B%283x%2B6%29+=+84 ALIGN=MIDDLE  ALT=\"%28x%2B6%29%2B%283x%2B6%29+=+84\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "Solve using basic algebra; then remember the answer to the question is Ben's age 6 years from now, which is x+6 -- not just x.<br><BR>\n" );
document.write( "Informally, using logical reasoning and simple arithmetic (good brain exercise!)....<br><BR>\n" );
document.write( "The sum of their ages 6 years from now will be 84, so the sum of their ages now (subtract 6 years for each of them) is 72.<br><BR>\n" );
document.write( "Since Ari is now 3 times as old as Ben, simple mental arithmetic tells us Ben is now 18 and Ari is 54.<br><BR>\n" );
document.write( "So Ben's age 6 years from now will be 18+6=24.<br><BR>\n" );
document.write( "If you completed solving the problem using the formal algebra method suggested above, you will see that the formal algebra used exactly the same calculations as the informal solution.<br><BR>\n" );
document.write( " </SPAN>\n" );
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