document.write( "Question 1176443: Hi
\n" ); document.write( "In a class of 40 the average score was 70.25. The average scores for boys and girls were 68 and 73 respectively. How many boys were in the class.
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Algebra.Com's Answer #803352 by ikleyn(52797) $\"\"$ $\"About$

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\n" ); document.write( "In a class of 40 the average score was 70.25.
\n" ); document.write( "The average scores for boys and girls were 68 and 73 respectively.
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document.write( "Let x be the number of boys;\r\n" );
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document.write( "then the number of girls is  (40-x).\r\n" );
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document.write( "Total scores of boys is 68x;  total scores of girls is 73*(40-x).\r\n" );
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document.write( "Total scores of the class is 40*70.25 = 2810.\r\n" );
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document.write( "The equation of total scores is\r\n" );
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document.write( "    68x + 73*(40-x) = 2810.\r\n" );
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document.write( "From the equation\r\n" );
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document.write( "    x =  = 22.\r\n" );
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document.write( "ANSWER.  There are  22  boys in the class.\r\n" );
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