document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=835590>Question 835590</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The average a,b, and c is 15. The average of a and b is 18. What is the value of c?<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #503634 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=503634\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The average a,b, and c is 15. The average of a and b is 18. What is the value of c?<BR>\n" );
document.write( "-------<BR>\n" );
document.write( "Equations:<BR>\n" );
document.write( "(a+b)/2 = 18<BR>\n" );
document.write( "So, a+b = 36<BR>\n" );
document.write( "-------<BR>\n" );
document.write( "(a+b+c)/3 = 15<BR>\n" );
document.write( "So, a+b+c = 45<BR>\n" );
document.write( "----<BR>\n" );
document.write( "Substitute for \"a+b\" and solve for \"c\":<BR>\n" );
document.write( "36 + c = 45<BR>\n" );
document.write( "c = 9<BR>\n" );
document.write( "===============<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "================= </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );