document.write( "Question 68121: Going into the final exam, which will count as 2 tests, Brooke has a test score of 80, 83,71,61, 95. What score does Brooke need on the final in order to have an average score of 80? \n" ); document.write( "
Algebra.Com's Answer #48394 by Edwin McCravy(20055)\"\" \"About 
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document.write( "Going into the final exam, which will\r\n" );
document.write( "count as 2 tests, Brooke has a test \r\n" );
document.write( "score of 80, 83,71,61, 95. What score\r\n" );
document.write( "does Brooke need on the final in \r\n" );
document.write( "order to have an average score of 80?\r\n" );
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document.write( "Let x = her final exam grade\r\n" );
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document.write( "           sum of all test grades  \r\n" );
document.write( "Average = ------------------------\r\n" );
document.write( "             number of tests\r\n" );
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document.write( "She has taken 5 tests already and the \r\n" );
document.write( "final exam is the same as if she took \r\n" );
document.write( "two more tests (7 in all) and made \r\n" );
document.write( "the same grade on both.  Using the \r\n" );
document.write( "above formula:\r\n" );
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document.write( "      80 + 83 + 71 + 61 + 95 + x + x\r\n" );
document.write( "80 = ---------------------------------\r\n" );
document.write( "                   7\r\n" );
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document.write( "      390 + 2x\r\n" );
document.write( "80 = ----------\r\n" );
document.write( "         7\r\n" );
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document.write( "Multiply both sides by 7 to clear of \r\n" );
document.write( "fractions\r\n" );
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document.write( "7·80 = 390 + 2x\r\n" );
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document.write( " 560 = 390 + 2x\r\n" );
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document.write( " 170 = 2x\r\n" );
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document.write( "  85 = x\r\n" );
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document.write( "She needs to make 85 on the final.\r\n" );
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document.write( "Edwin
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