Three Numbers in France

I wish to find three numbers of such nature that the first and the second with \(\frac{1}{2}\) of the third makes 20, and the second and the third with \(\frac{1}{3}\) of the first comes to 20, and the third plus the first and \(\frac{1}{4}\) of the second also equals 20.

Le Triparty en la science des nombres, Nicolas Chuquet, 1484

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