Washing the Dishes

Now there was a woman washing bowls by the river. An official came by and asked, "Why are there so many bowls?" The woman replied, "There were guests in the house." The official then asked, "How many guests?" The woman said, "I do not know but: every two persons had a bowl of rice; every three persons had a bowl of soup and every four persons had a bowl of meat, sixty-five bowls were used altogether." How many guests were there?

Sunzi suan jing (Mathematical Classic of Master Sun), Sunzi, c. 400 CE

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