On the Run

A certain slave fled from Milan to Naples going \(\frac{1}{10}\) of the whole journey each day.  At the beginning of the third day, his master sent a slave after him and this slave went \(\frac{1}{7}\) of the whole journey each day.  I do not know how far it is from Milan to Naples, but I wish to know when the latter overtook him.

Practica Arithmetice, Cardano, 1539

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