document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=257409>Question 257409</A>: <I><SPAN STYLE=\"word-break: break-all;\"> if each student in a class sends a card to every one of his class mate the total number of cards sent out will be rs 1560. find the number of student in the class. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #189444 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley77><B>checkley77(12844)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley77><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=189444\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x be the number of students in the class<BR>\n" );
document.write( "Let (x-1) be the number of cards each student sends (everyone but themselves)<BR>\n" );
document.write( "x(x-1)=1,560<BR>\n" );
document.write( "x^2-x-1,560=0<BR>\n" );
document.write( "(x-40)(x+39)=0<BR>\n" );
document.write( "x-40=0<BR>\n" );
document.write( "x=40 students are in the class.<BR>\n" );
document.write( "Proof:<BR>\n" );
document.write( "40*39=1,560<BR>\n" );
document.write( "1,560=1,560 </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );