document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=823754>Question 823754</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What is the detail solution of this question:\r<BR>\n" );
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document.write( "In a class of 50 students the boys obtained an average grade of 80 points for the Maths<BR>\n" );
document.write( "test and the girls obtained an average grade of 90 points for the same test. If the boys had scored 5%<BR>\n" );
document.write( "more on average and the girls had scored 10% more on average, then the whole class would have<BR>\n" );
document.write( "got 350 extra points. How many boys are there in this class? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #495759 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=495759\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In a class of 50 students the boys obtained an average grade of 80 points for the Maths test and the girls obtained an average grade of 90 points for the same test.<BR>\n" );
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document.write( "# of boys + # of girls = 50<BR>\n" );
document.write( "b + g = 50<BR>\n" );
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document.write( "Points DATA:<BR>\n" );
document.write( "Boy's point total:: 80b<BR>\n" );
document.write( "Girl's point total: 90g<BR>\n" );
document.write( "Original total points:: 80b + 90g<BR>\n" );
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document.write( "If the boys had scored 5% more on average and the girls had scored 10% more on average, then the whole class would have got 350 extra points.<BR>\n" );
document.write( "Boys point total would be  1.05*80b = 84b <BR>\n" );
document.write( "Girls point total would be  1.10*90g = 99g<BR>\n" );
document.write( "New number of points = 84b+99g<BR>\n" );
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document.write( "How many boys are there in this class?<BR>\n" );
document.write( "New number of points - original # of points = 350<BR>\n" );
document.write( "[84b + 99g] - [80b+90g] = 350<BR>\n" );
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document.write( "Two equations from the DATA::<BR>\n" );
document.write( "4b + 9g = 350<BR>\n" );
document.write( "b  +  g = 50<BR>\n" );
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document.write( "Modify for elimination:<BR>\n" );
document.write( "4b + 9g = 350<BR>\n" );
document.write( "9b + 9g = 450<BR>\n" );
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document.write( "5b = 100<BR>\n" );
document.write( "b = 20 (# of boys)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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