document.write( "Question 422094: there is 100 kids in class taking the test 80% is average for the boys 70% is average for the girls the average of the class is 76% how many girls are in the class \n" ); document.write( "
Algebra.Com's Answer #294666 by ankor@dixie-net.com(22740)\"\" \"About 
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there is 100 kids in class taking the test
\n" ); document.write( " 80% is average for the boys 70% is average for the girls
\n" ); document.write( " the average of the class is 76% how many girls are in the class
\n" ); document.write( ":
\n" ); document.write( "Let x = no. of girls in the class
\n" ); document.write( "then
\n" ); document.write( "(100-x) = no. of boys in the class
\n" ); document.write( ":
\n" ); document.write( "\"%2880%28100-x%29+%2B+70x%29%2F100\" = 76
\n" ); document.write( "Multiply by 100
\n" ); document.write( "80(100-x) + 70x = 100(76)
\n" ); document.write( "8000 - 80x + 70x = 7600
\n" ); document.write( "-80x + 70x = 7600 - 8000
\n" ); document.write( "-10x = -400
\n" ); document.write( "x = \"%28-400%29%2F%28-10%29\"
\n" ); document.write( "x = +40 girls
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check solution, (60 boys, obviously)
\n" ); document.write( "\"%2880%2860%29+%2B+70%2840%29%29%2F100\" =
\n" ); document.write( "\"%284800%2B2800%29%2F100\" = 76\r
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