document.write( "Question 1131613: At present Allen is 10 years younger than Scott. Ten years from now, Scott’s age will be 3 times the present age of Allen. Find the present age of Allen and Scott. \n" ); document.write( "

Algebra.Com's Answer #748303 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( " Since the solution by @addingup is ABSOLUTELY WRONG, I came to bring the correct solution.\r
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document.write( "A = S-10      (1)\r\n" );
document.write( "S+10 = 3A     (2)\r\n" );
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document.write( "Substitute expression  A = S-10  from eq(1) into eq(2), replacing A in equation (2).\r\n" );
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document.write( "S + 10 = 3*(S-10)\r\n" );
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document.write( "S + 10 = 3S - 30\r\n" );
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document.write( "10 + 30 = 3S - S\r\n" );
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document.write( "2S = 40   ====>  S = 40/2 = 20.\r\n" );
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document.write( "ANSWER.  Scott is 20 years now.  Allen is 20-10 = 10 years now.\r\n" );
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document.write( "Check.   Eq(1):  A = S-10:   10 = 20-10      ! Correct !\r\n" );
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document.write( "         Eq(2):  S+10 = 3A:  20+10 = 3*10    ! Correct !\r\n" );
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