document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=504466>Question 504466</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The average of a class of 40 students is 12 years. if the teacher's age is also included, the average age increases by one year. The teacher's age is? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #339613 by </B><A HREF=/tutors/aboutme.mpl?userid=geetha_rama><B>geetha_rama(94)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=geetha_rama><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=339613\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Assume x be the Age of the student.<BR>\n" );
document.write( "Average age of 40 students = 12 years<BR>\n" );
document.write( "Total age is :<BR>\n" );
document.write( "  40x = 12*40<BR>\n" );
document.write( "40x = 480  -> Equation 1\r<BR>\n" );
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document.write( "Let teachers age be y<BR>\n" );
document.write( "Average age of 41 people (40 studenets + 1 teacher) = 13 years<BR>\n" );
document.write( "Hence total age <BR>\n" );
document.write( "   40x + y = 533  -> Equation 2 \r<BR>\n" );
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document.write( "Subtracting equation 1 from equation 2, we get<BR>\n" );
document.write( " y = 53\r<BR>\n" );
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document.write( "Age of teacher  = 53 years </SPAN>\n" );
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