document.write( "Question 682965: at a certain university 540 students are math and computer science majors. if 300 are majoring in math and 120 are majoring in both, how many are majoring in computer science? \n" ); document.write( "
Algebra.Com's Answer #423445 by Edwin McCravy(20063)\"\" \"About 
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document.write( "Let x = The number of students majoring in math ONLY\r\n" );
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document.write( "let y = The number of students majoring in computer science ONLY\r\n" );
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document.write( "Let z - The number of students majoring in computer science.\r\n" );
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document.write( " +  = \r\n" );
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document.write( " +  =\r\n" );
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document.write( " +  + = \r\n" );
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document.write( "So we substitute the corresponding numbers or unknowns for\r\n" );
document.write( "the above three statements and we have this system of equations:\r\n" );
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document.write( "x + 120 = 300\r\n" );
document.write( "y + 120 = z\r\n" );
document.write( "x + 120 + y = 540\r\n" );
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document.write( "Solve that and get x = 180, y = 240, and z = 360\r\n" );
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document.write( "The answer asked for was z, which is 360.\r\n" );
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document.write( "Edwin
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