document.write( "Question 1205894: A and B are running a race. A has an 84 feet head start when they begin running.
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Algebra.Com's Answer #842978 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "A and B are running a race. A has an 84 feet head start when they begin running.
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document.write( "Let d be the distance A runs before B overtakes A.\r\n" );
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document.write( "Then the distance that B will cover at that time moment is (d+84) feet.\r\n" );
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document.write( "Their speeds are in the ratio  =  = .\r\n" );
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document.write( "They spend the same time - THEREFORE, the ratio of distances is the same \r\n" );
document.write( "as the ratio of their speeds.\r\n" );
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document.write( "So, we write this proportion\r\n" );
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document.write( "     = .\r\n" );
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document.write( "Cross-multiply\r\n" );
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document.write( "    3d = 2*(d+84).\r\n" );
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document.write( "Simplify and find d\r\n" );
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document.write( "    3d = 2d + 2*84\r\n" );
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document.write( "    3d - 2d = 2*84\r\n" );
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document.write( "       d    = 168.\r\n" );
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document.write( "ANSWER.  The distance A runs before B overtakes A is 168 feet.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "Just fixed my error.\r
\n" ); document.write( "\n" ); document.write( "Thanks to @greenestamps !\r
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