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The epitaph of Diophantus

agesfractionsalgebrahistory

A riddle said to be carved on the tomb of the mathematician Diophantus reads, in modern words:

"God granted him boyhood for a sixth of his life; after a twelfth more his cheeks grew a beard; after a seventh more he married; five years later a son was born; the son lived to half his father's final age; and the father died four years after his son."

How old was Diophantus when he died?

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Let his age at death be x and add up all the pieces of his life.

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The Chevalier de Mere ProblemThe Substitution That Collapses the AlgebraConverting Fractions, Decimals and PercentagesFunctional EquationsNested Radicals and Infinite Fractions

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