document.write( "Question 1044329: John is athird of his father's age.In ten years time,he will be ahalf of his father's age then.How old is john \n" ); document.write( "

Algebra.Com's Answer #659601 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "John is athird of his father's age. In ten years time, he will be ahalf of his father's age then.How old is john
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document.write( "F = 3J            (1)    (J = John's present age; F = father's present age)\r\n" );
document.write( "F+10 = 2(J+10).   (2)    ( \"In ten years time, John will be ahalf of his father's age then\" )\r\n" );
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document.write( "Substitute (1) into (2). You will get\r\n" );
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document.write( "3J + 10 = 2(J + 10),   or\r\n" );
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document.write( "3J + 10 = 2J + 20  --->  J = 20 - 10  --->  J = 10.\r\n" );
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document.write( "Answer.  John is ten years now. His father is 3*10 = 30 years now.\r\n" );
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\n" ); document.write( "\n" ); document.write( "For age problems see the lessons \r
\n" ); document.write( "\n" ); document.write( "    - Age problems and their solutions\r
\n" ); document.write( "\n" ); document.write( "    - A fresh formulation of a traditional age problem\r
\n" ); document.write( "\n" ); document.write( "    - Really intricate age word problem\r
\n" ); document.write( "\n" ); document.write( "    - Selected age word problems from the archive\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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