document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1039304>Question 1039304</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Following table gives study hours in a week by 100 students of class XI.Find out the arithmetic mean by step deviation method:<BR>\n" );
document.write( "Hours | No. of students<BR>\n" );
document.write( "<10   |  2<BR>\n" );
document.write( "<20   |  6<BR>\n" );
document.write( "<30   |  35<BR>\n" );
document.write( "<40   |  62<BR>\n" );
document.write( "<50   |  80 <BR>\n" );
document.write( "<60   |  100 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #654989 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=654989\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let the class interval <40 be the zero basis for the step deviation.<BR>\n" );
document.write( "Note that the class mark for the basis class interval is 35, and the class width is 10.\r<BR>\n" );
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document.write( "d   |  f  | df<BR>\n" );
document.write( "----------------<BR>\n" );
document.write( "-3 | 2  | -6<BR>\n" );
document.write( "-2 | 4  | -8<BR>\n" );
document.write( "-1 | 29 | -29<BR>\n" );
document.write( "0  | 27 | 0<BR>\n" );
document.write( "1  | 18 | 18<BR>\n" );
document.write( "2  | 20 | 40 <BR>\n" );
document.write( "----------------<BR>\n" );
document.write( "   | 100 |15\r<BR>\n" );
document.write( "\n" );
document.write( "==> Mean  = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=35%2Bsum%28df%2C+i=1%2C6%29%2FN+=+35+%2B+%2815%2F100%29%2A10+=+36.5 ALIGN=MIDDLE  ALT=\"35%2Bsum%28df%2C+i=1%2C6%29%2FN+=+35+%2B+%2815%2F100%29%2A10+=+36.5\"   DISABLED_style= \"max-width:90%; height:auto;\" >. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );