document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=993340>Question 993340</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A teacher and his assistant can grade all student's exams in 4 hours. When the assistant does the grading by himself, it takes him an hour longer than it takes the teacher alone to do the grading. Find how many hours it takes the teacher to do the grading by himself.\r<BR>\n" );
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document.write( "Type your numerical answer rounded to one decimal </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #612592 by </B><A HREF=/tutors/aboutme.mpl?userid=anand429><B>anand429(138)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=anand429><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=anand429><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=612592\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let teacher can grade t students per hour and assistant can grade s students per hour<BR>\n" );
document.write( "In 4 hours, no. of students graded = 4t + 4s<BR>\n" );
document.write( "In 5 hours assistant can grade alone<BR>\n" );
document.write( "so no. of students as per him = 5s<BR>\n" );
document.write( "so, 4t + 4s = 5s<BR>\n" );
document.write( "=> 4t = s<BR>\n" );
document.write( "So time taken by teacher alone= (4t + 4s)/t<BR>\n" );
document.write( "= (4t + 16t)/t<BR>\n" );
document.write( "=20t/t<BR>\n" );
document.write( "=20 hours.<BR>\n" );
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