Legend has it that the great geometer Euclid composed a puzzle which went as follows...
A mule and a donkey were stumbling along the road, each carrying several identical heavy sacks.
The donkey starting complaining, making a horrible groaning noise, and eventually the mule got fed up.
‘What are you complaining for? If you gave me one sack, I’d have twice as many as you! And if I gave you one sack, we’d be carrying the same load.’
How many sacks were the donkey and the mule carrying?
As seen on page 224, Professor Stewart's Hoard of Mathematical Treasures