document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=259964>Question 259964</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The average of s and t is 12, and the average of s and t and u is 15. What is the value of u?\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #191407 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=191407\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> (s+t)/2  = 12  ----------1<BR>\n" );
document.write( "(s+t+u)/3  = 15 -------- 2\r<BR>\n" );
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document.write( "s+t= 12*2=24 from equation 1<BR>\n" );
document.write( "substitute the vale of s+t in equation 2\r<BR>\n" );
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document.write( "(24+u) / 3  = 15<BR>\n" );
document.write( "24+u = 15*3=45<BR>\n" );
document.write( "u=45-24<BR>\n" );
document.write( "u=21 </SPAN>\n" );
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