document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=942477>Question 942477</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Three years ago the average age of A and B was 18 years. While C joining them now, the average<BR>\n" );
document.write( "becomes 22 years. How old (in years) is C now? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #574543 by </B><A HREF=/tutors/aboutme.mpl?userid=macston><B>macston(5194)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=macston><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=macston><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=574543\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If three years ago the average was 18, today the average is 21 so<BR>\n" );
document.write( "(A+B)/2=21 <BR>\n" );
document.write( "A+B=42<BR>\n" );
document.write( "with C the average is 22 so<BR>\n" );
document.write( "(A+B+C)/3=22<BR>\n" );
document.write( "A+B+C=66 Substitute A+B from above<BR>\n" );
document.write( "(A+B)+C=66<BR>\n" );
document.write( "42+C=66 subtract 42 from each side<BR>\n" );
document.write( "C=24 so C is currently 24 years old </SPAN>\n" );
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