document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=839594>Question 839594</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the mean weight of 150 students in a certain class is 30kg. the mean weight of the boys in the class is 40kg and the girls is 25kg.Find the number of the boys and girls in the class<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 #505800 by </B><A HREF=/tutors/aboutme.mpl?userid=LinnW><B>LinnW(1048)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=LinnW><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=LinnW><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=505800\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Total weight of class = 150*30 = 4500<BR>\n" );
document.write( "Set b = number of boys<BR>\n" );
document.write( " g = number of girls<BR>\n" );
document.write( "40b + 25g = 4500 , 40kg x number of boys + 25kg x number of girs<BR>\n" );
document.write( "also<BR>\n" );
document.write( "30b + 30g = 4500<BR>\n" );
document.write( "Since each left side = 4500,<BR>\n" );
document.write( "30b + 30g = 40b + 25g<BR>\n" );
document.write( "add -30b to each side<BR>\n" );
document.write( "30g = 10b + 25g<BR>\n" );
document.write( "add -25g to each side<BR>\n" );
document.write( "5g = 10b<BR>\n" );
document.write( "g = 2b<BR>\n" );
document.write( "substitute 2b for g in 30b + 30g = 4500<BR>\n" );
document.write( "30b +30(2b) = 4500<BR>\n" );
document.write( "30b + 60b = 4500<BR>\n" );
document.write( "90b = 4500<BR>\n" );
document.write( "divide each side by 90<BR>\n" );
document.write( "b = 50<BR>\n" );
document.write( "since g = 2b,<BR>\n" );
document.write( "g = 100 </SPAN>\n" );
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