document.write( "Question 781909: Diophantus's youth lasted one sixth of his life. He grew a beard after one twelfth more. After one seventh more of his life, he married. 5 years later, he and his wife had a son. The son lived exactly one half as long as his father, and Diophantus died four years after his son. \r
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Algebra.Com's Answer #476155 by ankor@dixie-net.com(22740)\"\" \"About 
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Diophantus's youth lasted one sixth of his life.
\n" ); document.write( " He grew a beard after one twelfth more.
\n" ); document.write( " After one seventh more of his life, he married.
\n" ); document.write( " 5 years later, he and his wife had a son.
\n" ); document.write( " The son lived exactly one half as long as his father, and Diophantus died four years after his son.\r
\n" ); document.write( "\n" ); document.write( "How many years did Diophantus live?\r
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\n" ); document.write( "\n" ); document.write( "Let x = his final age
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\n" ); document.write( "a lengthy but simple equation
\n" ); document.write( "Final age = child + youth + bach + marriage + son's age + 4
\n" ); document.write( "x = \"1%2F6\"x + \"1%2F12\"x + \"1%2F7\"x + 5 + \"1%2F2\"x + 4
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\n" ); document.write( "Common denominator of 12*7 = 84
\n" ); document.write( "x = \"14%2F84\"x + \"7%2F84\"x + \"12%2F84\"x + 5 + \"42%2F84\"x + 4
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\n" ); document.write( "x = \"75%2F84\"x + 9
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\n" ); document.write( "\"84%2F84\"x - \"75%2F84\"x = 9
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\n" ); document.write( "\"9%2F84\"x = 9
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\n" ); document.write( "x = 9 * \"84%2F9\"
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\n" ); document.write( "x = 84 is his final age
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\n" ); document.write( "Check:
\n" ); document.write( "14 + 7 + 12 + 5 + 42 + 4 = 84
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